Why is my ngrx parameter showing an error?

I have the following service that signs up a user:

public signup = (user:UserModel) => {
    console.log('UserService.user', user)

    return this.httpClient.post<{user:UserModel}>(this.url, {user}).pipe(
      tap(user => {
        console.log('UserService.user tap', user)
        this.store.dispatch(StoreUser({user}))
      })
   )
 }

I am trying to dispatch the user received from the backend to the StoreUser action but I am getting an error. The user parameter in this line this.store.dispatch(StoreUser({user}) has a red line indicating an error. The error which appears to be a type error is shown below:

Type '{ user: UserModel; }' is missing the following properties from type 'UserModel': firstName, lastName, password, email, tokents(2739) user.actions.ts(6, 13): The expected type comes from property 'user' which is declared here on type '{ user: UserModel; }' (property) user: UserModel

This is the UserModel class:

export class UserModel {
    public firstName:string = '';
    public lastName:string = '';
    public password:string = '';
    public email:string = '';
    public token:string = '';
}

This is the action:

import { createAction, props } from "@ngrx/store";
import { UserModel } from "./user.model";

export const StoreUser = createAction(
    '[Store user] Store user',
    props<{ user:UserModel }>()
  );

public signin = (user:UserModel) => {
return this.httpClient.put<UserModel>(this.url, {user}).pipe(
  tap(user => {
    console.log('UserService.user tap: ', user)
    this.store.dispatch(StoreUser({user: user}))
  }),
  catchError(error => {
    console.log('error', error)
    this.toastr.warning(error.error, '');
    throw error;
  })    
)

}

Model:

export class UserModel {
    public firstName?:string;
    public lastName?:string;
    public password?:string;
    public email?:string;
    public token?:string;
}

Action:

export const StoreUser = createAction(
'[Store user] Store user',
props<{ user:UserModel}>()

);