Proxy error when accessing controller in ASP.NET core + angular

Question

I’m sending a request for a project that has the structure:

• Frontend: Angular
• Backend: ASP.NET Core

When sending this request, my controller returns the following message:

System.Net.Http.Httprequestexception: Failed to proxy the request to http: //api / product / Insert, because the request to the proxy target failed. Check that the proxy target server is running and Accepting requests to http: //localhost: 50005 /.

Looking for any resolution I saw on the microsoft site the inclusion in startup.Cs of a sp.UseProxy.. then tried with only one, but none solved my problem.

spa.UseProxyToSpaDevelopmentServer ("http//localhost:50005/");

and

spa.UseProxyToSpaDevelopmentServer ("http: // localhost:4200/");

Angular code:

import { Inject, Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { HttpHeaders } from '@angular/common/http';
import { Observable } from 'rxjs';
import { Product } from './product';

const headers: HttpHeaders = new HttpHeaders();
headers.set('Content-Type', 'application/x-www-form-urlencoded');

@Injectable({
   providedIn: 'root'
})

export class ProductService {

 url: string;
 http: any;
 constructor(http: HttpClient, @Inject('BASE_URL') baseUrl: string) {
   this.http = http;
   this.url = baseUrl;
 }


 insertProd(product: Product): Observable<Product>{
   return this.http.post(this.url + '/api/product/insert', product, headers);  
  }
 }