I’m using json-server as a fake api, and when making the POST request, my ids are not being generated automatically, note that they are already as a String, which is as recommended in the documentation.

My class user

export class User {
  public id: String = ''
  public name: String = ''
  public phone: String = ''
  public email: String = ''
  public cpf: String = ''
  public password: String = ''
}

my class in which I assign the form data to user and my method that accesses the post in the service

 onSubmit(): void {

  if(this.addressForm.controls['name'].value)
  this.user.name = this.addressForm.controls['name'].value

  if(this.addressForm.controls['email'].value)
  this.user.email = this.addressForm.controls['email'].value

  if(this.addressForm.controls['phone'].value)
  this.user.phone = this.addressForm.controls['phone'].value

  if(this.addressForm.controls['cpf'].value)
  this.user.cpf = this.addressForm.controls['cpf'].value

 if(this.addressForm.controls['password'].value)
  this.user.password = this.addressForm.controls['password'].value

console.log(this.user)


   this.service.addUser(this.user).subscribe({  
      next: (response) => {
      console.log(response)
      alert('Dado registrado com sucesso')
   },
     error: (erro: any) => { // error -> Tratamento de exceção do subscribe
     console.log(erro)
     alert('Ocorreu algum erro')
   }
  })   
  }

from 10 to 13 I manually put the data in my db.json, after that we can notice that the id is not coming automatically

{
"id": "10",
"firstName": "Bruno",
"email": "[email protected]",
"phone": "323",
"cpf": "05126769685",
"password": "fdsfds"
  },
{
"id": "11",
"firstName": "Bruno",
"email": "[email protected]",
"phone": "323",
"cpf": "05126769685",
"password": "fdsfds"
 },
{
"id": "12",
"firstName": "Bruno",
"email": "[email protected]",
"phone": "323",
"cpf": "05126769685",
"password": "fdsfds"
  },
 {
"id": "13",
"firstName": "Bruno",
"email": "[email protected]",
"phone": "323",
"cpf": "05126769685",
"password": "fdsfds"
 },
{
"id": "",
"name": "teste",
"phone": "1111111111",
"email": "[email protected]",
"cpf": "18361591885",
"password": "111"
 }
]