diff --git a/frontend/src/client/core/request.ts b/frontend/src/client/core/request.ts
index 99d38b4..6abb0e8 100644
--- a/frontend/src/client/core/request.ts
+++ b/frontend/src/client/core/request.ts
@@ -1,9 +1,9 @@
 import axios from "axios"
 import type {
   AxiosError,
+  AxiosInstance,
   AxiosRequestConfig,
   AxiosResponse,
-  AxiosInstance,
 } from "axios"
 
 import { ApiError } from "./ApiError"
@@ -151,12 +151,12 @@ export const getHeaders = async (
     )
 
   if (isStringWithValue(token)) {
-    headers["Authorization"] = `Bearer ${token}`
+    headers.Authorization = `Bearer ${token}`
   }
 
   if (isStringWithValue(username) && isStringWithValue(password)) {
     const credentials = base64(`${username}:${password}`)
-    headers["Authorization"] = `Basic ${credentials}`
+    headers.Authorization = `Basic ${credentials}`
   }
 
   if (options.body !== undefined) {
diff --git a/frontend/src/client/models.ts b/frontend/src/client/models.ts
index a8e1b7a..2c8074d 100644
--- a/frontend/src/client/models.ts
+++ b/frontend/src/client/models.ts
@@ -19,8 +19,8 @@ export type ItemCreate = {
 export type ItemPublic = {
   title: string
   description?: string | null
-  id: number
-  owner_id: number
+  id: string
+  owner_id: string
 }
 
 export type ItemUpdate = {
@@ -65,7 +65,7 @@ export type UserPublic = {
   is_active?: boolean
   is_superuser?: boolean
   full_name?: string | null
-  id: number
+  id: string
 }
 
 export type UserRegister = {
diff --git a/frontend/src/client/schemas.ts b/frontend/src/client/schemas.ts
index 0043c1b..9e92efd 100644
--- a/frontend/src/client/schemas.ts
+++ b/frontend/src/client/schemas.ts
@@ -65,12 +65,15 @@ export const $ItemCreate = {
     title: {
       type: "string",
       isRequired: true,
+      maxLength: 255,
+      minLength: 1,
     },
     description: {
       type: "any-of",
       contains: [
         {
           type: "string",
+          maxLength: 255,
         },
         {
           type: "null",
@@ -85,12 +88,15 @@ export const $ItemPublic = {
     title: {
       type: "string",
       isRequired: true,
+      maxLength: 255,
+      minLength: 1,
     },
     description: {
       type: "any-of",
       contains: [
         {
           type: "string",
+          maxLength: 255,
         },
         {
           type: "null",
@@ -98,12 +104,14 @@ export const $ItemPublic = {
       ],
     },
     id: {
-      type: "number",
+      type: "string",
       isRequired: true,
+      format: "uuid",
     },
     owner_id: {
-      type: "number",
+      type: "string",
       isRequired: true,
+      format: "uuid",
     },
   },
 } as const
@@ -115,6 +123,8 @@ export const $ItemUpdate = {
       contains: [
         {
           type: "string",
+          maxLength: 255,
+          minLength: 1,
         },
         {
           type: "null",
@@ -126,6 +136,7 @@ export const $ItemUpdate = {
       contains: [
         {
           type: "string",
+          maxLength: 255,
         },
         {
           type: "null",
@@ -169,6 +180,8 @@ export const $NewPassword = {
     new_password: {
       type: "string",
       isRequired: true,
+      maxLength: 40,
+      minLength: 8,
     },
   },
 } as const
@@ -191,10 +204,14 @@ export const $UpdatePassword = {
     current_password: {
       type: "string",
       isRequired: true,
+      maxLength: 40,
+      minLength: 8,
     },
     new_password: {
       type: "string",
       isRequired: true,
+      maxLength: 40,
+      minLength: 8,
     },
   },
 } as const
@@ -204,6 +221,8 @@ export const $UserCreate = {
     email: {
       type: "string",
       isRequired: true,
+      format: "email",
+      maxLength: 255,
     },
     is_active: {
       type: "boolean",
@@ -218,6 +237,7 @@ export const $UserCreate = {
       contains: [
         {
           type: "string",
+          maxLength: 255,
         },
         {
           type: "null",
@@ -227,6 +247,8 @@ export const $UserCreate = {
     password: {
       type: "string",
       isRequired: true,
+      maxLength: 40,
+      minLength: 8,
     },
   },
 } as const
@@ -236,6 +258,8 @@ export const $UserPublic = {
     email: {
       type: "string",
       isRequired: true,
+      format: "email",
+      maxLength: 255,
     },
     is_active: {
       type: "boolean",
@@ -250,6 +274,7 @@ export const $UserPublic = {
       contains: [
         {
           type: "string",
+          maxLength: 255,
         },
         {
           type: "null",
@@ -257,8 +282,9 @@ export const $UserPublic = {
       ],
     },
     id: {
-      type: "number",
+      type: "string",
       isRequired: true,
+      format: "uuid",
     },
   },
 } as const
@@ -268,16 +294,21 @@ export const $UserRegister = {
     email: {
       type: "string",
       isRequired: true,
+      format: "email",
+      maxLength: 255,
     },
     password: {
       type: "string",
       isRequired: true,
+      maxLength: 40,
+      minLength: 8,
     },
     full_name: {
       type: "any-of",
       contains: [
         {
           type: "string",
+          maxLength: 255,
         },
         {
           type: "null",
@@ -294,6 +325,8 @@ export const $UserUpdate = {
       contains: [
         {
           type: "string",
+          format: "email",
+          maxLength: 255,
         },
         {
           type: "null",
@@ -313,6 +346,7 @@ export const $UserUpdate = {
       contains: [
         {
           type: "string",
+          maxLength: 255,
         },
         {
           type: "null",
@@ -324,6 +358,8 @@ export const $UserUpdate = {
       contains: [
         {
           type: "string",
+          maxLength: 40,
+          minLength: 8,
         },
         {
           type: "null",
@@ -340,6 +376,7 @@ export const $UserUpdateMe = {
       contains: [
         {
           type: "string",
+          maxLength: 255,
         },
         {
           type: "null",
@@ -351,6 +388,8 @@ export const $UserUpdateMe = {
       contains: [
         {
           type: "string",
+          format: "email",
+          maxLength: 255,
         },
         {
           type: "null",
diff --git a/frontend/src/client/services.ts b/frontend/src/client/services.ts
index e4b8138..be024e4 100644
--- a/frontend/src/client/services.ts
+++ b/frontend/src/client/services.ts
@@ -4,20 +4,20 @@ import { request as __request } from "./core/request"
 
 import type {
   Body_login_login_access_token,
+  ItemCreate,
+  ItemPublic,
+  ItemUpdate,
+  ItemsPublic,
   Message,
   NewPassword,
   Token,
-  UserPublic,
   UpdatePassword,
   UserCreate,
+  UserPublic,
   UserRegister,
-  UsersPublic,
   UserUpdate,
   UserUpdateMe,
-  ItemCreate,
-  ItemPublic,
-  ItemsPublic,
-  ItemUpdate,
+  UsersPublic,
 } from "./models"
 
 export type TDataLoginAccessToken = {
@@ -50,7 +50,7 @@ export class LoginService {
       formData: formData,
       mediaType: "application/x-www-form-urlencoded",
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -85,7 +85,7 @@ export class LoginService {
         email,
       },
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -106,7 +106,7 @@ export class LoginService {
       body: requestBody,
       mediaType: "application/json",
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -128,7 +128,7 @@ export class LoginService {
         email,
       },
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -151,14 +151,14 @@ export type TDataRegisterUser = {
   requestBody: UserRegister
 }
 export type TDataReadUserById = {
-  userId: number
+  userId: string
 }
 export type TDataUpdateUser = {
   requestBody: UserUpdate
-  userId: number
+  userId: string
 }
 export type TDataDeleteUser = {
-  userId: number
+  userId: string
 }
 
 export class UsersService {
@@ -180,7 +180,7 @@ export class UsersService {
         limit,
       },
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -201,7 +201,7 @@ export class UsersService {
       body: requestBody,
       mediaType: "application/json",
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -248,7 +248,7 @@ export class UsersService {
       body: requestBody,
       mediaType: "application/json",
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -269,7 +269,7 @@ export class UsersService {
       body: requestBody,
       mediaType: "application/json",
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -290,7 +290,7 @@ export class UsersService {
       body: requestBody,
       mediaType: "application/json",
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -312,7 +312,7 @@ export class UsersService {
         user_id: userId,
       },
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -336,7 +336,7 @@ export class UsersService {
       body: requestBody,
       mediaType: "application/json",
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -356,7 +356,7 @@ export class UsersService {
         user_id: userId,
       },
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -382,7 +382,7 @@ export class UtilsService {
         email_to: emailTo,
       },
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -396,14 +396,14 @@ export type TDataCreateItem = {
   requestBody: ItemCreate
 }
 export type TDataReadItem = {
-  id: number
+  id: string
 }
 export type TDataUpdateItem = {
-  id: number
+  id: string
   requestBody: ItemUpdate
 }
 export type TDataDeleteItem = {
-  id: number
+  id: string
 }
 
 export class ItemsService {
@@ -425,7 +425,7 @@ export class ItemsService {
         limit,
       },
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -446,7 +446,7 @@ export class ItemsService {
       body: requestBody,
       mediaType: "application/json",
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -466,7 +466,7 @@ export class ItemsService {
         id,
       },
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -490,7 +490,7 @@ export class ItemsService {
       body: requestBody,
       mediaType: "application/json",
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
@@ -510,7 +510,7 @@ export class ItemsService {
         id,
       },
       errors: {
-        422: `Validation Error`,
+        422: "Validation Error",
       },
     })
   }
diff --git a/frontend/src/components/Common/DeleteAlert.tsx b/frontend/src/components/Common/DeleteAlert.tsx
index c89d141..1528fc5 100644
--- a/frontend/src/components/Common/DeleteAlert.tsx
+++ b/frontend/src/components/Common/DeleteAlert.tsx
@@ -16,7 +16,7 @@ import useCustomToast from "../../hooks/useCustomToast"
 
 interface DeleteProps {
   type: string
-  id: number
+  id: string
   isOpen: boolean
   onClose: () => void
 }
@@ -30,7 +30,7 @@ const Delete = ({ type, id, isOpen, onClose }: DeleteProps) => {
     formState: { isSubmitting },
   } = useForm()
 
-  const deleteEntity = async (id: number) => {
+  const deleteEntity = async (id: string) => {
     if (type === "Item") {
       await ItemsService.deleteItem({ id: id })
     } else if (type === "User") {