At the time of implementing pipe in the ngrx it is showing error Angular 18

Cannot read properties of undefined (reading 'pipe')

this is the code I have written

register$ = createEffect(():any=>{
this.actions$.pipe(
ofType(registerUser),
mergeMap(action=>
this.userService.userRegister(action.firstName,action.lastName,action.email,action.phone,action.password).pipe(
map(user=> registerUserSuccess({user:user}))
)
)
)
})

export class UserService {

constructor(private readonly apollo: Apollo) {
}
userRegister(firstName:string,lastName:string,email:string,phone:number,password:string):Observable<any> {
return this.apollo.mutate({
mutation: REGISTER_USER,
variables: { userInput: { firstName, email, lastName, phone, password } },
})

}


How to solve this problem

Continue reading...