[Solved] Angular Error: Class incorrectly implements interface ResolveFn

Hi,

I have error in the below code but not sure where to look for error!

Class 'PropertyDetailResolverService' incorrectly implements interface 'ResolveFn<Property>'.

Type 'PropertyDetailResolverService' provides no match for the signature '(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Property | Observable<Property> | Promise<...>'.ts(2420)

import { Injectable } from '@angular/core';
import { ActivatedRouteSnapshot, ResolveFn, RouterStateSnapshot } from '@angular/router';
import { Property } from '../../model/property';
import { HousingService } from '../../services/housing.service';
import { Observable } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class PropertyDetailResolverService implements ResolveFn<Property>{

constructor(private housingService: HousingService) { }

resolvefn(route: ActivatedRouteSnapshot, state: RouterStateSnapshot):

  Observable<Property>|Property {
    
    const propId = route.params['id'];
    return this.housingService.getProperty(propId)
  }
}