Type 'Observable<{ "CardModel": { "theme": string; "title": string; "description": string; }[]; }>' is not assignable to type 'Observable<CardModel[]>'.

@Injectable()
export class PlanService {
  constructor() {}

  public getPlans(): Observable<CardModel[]> {
    return of(PlanServiceMock.plansMockData);
  }
}

export class PlanServiceMock {
  public static readonly plansMockData = {
    "CardModel": [
        {
            "theme": "",
            "title": "this is title",
            "description": "this is description"
        }
    ]
  };
}