Error consuming WebApi and testing it on localhost

I have a WebApi, where I make a query to Sql Server, in other controllers there is no problem, it is done correctly, but in this I skip the following error

  

An error has occurred.   Multiple actions were found that match the request: Get on type   WebApiFacturador.Controllers.ConexionController DatosEmpresa on type   WebApiFacturador.Controllers.ConexionController   System.InvalidOperationException    in   System.Web.Http.Controllers.ApiControllerActionSelector.ActionSelectorCacheItem.SelectAction (HttpControllerContext   controllerContext) in   System.Web.Http.Controllers.ApiControllerActionSelector.SelectAction (HttpControllerContext   controllerContext) in   System.Web.Http.ApiController.ExecuteAsync (HttpControllerContext   controllerContext, CancellationToken cancellationToken) in   System.Web.Http.Dispatcher.HttpControllerDispatcher.d__1.MoveNext ()    

This is my code

    using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using WebApiFacturador.Datos;

namespace WebApiFacturador.Controllers
{
    public class ConexionController : ApiController
    {
        // GET: api/Conexion
        public IEnumerable<string> Get()
        {
            return new string[] { "value1", "value2" };
        }

        // GET: api/Conexion/5
        public string Get(int id)
        {
            return "value";
        }

        // POST: api/Conexion
        public void Post([FromBody]string value)
        {
        }

        // PUT: api/Conexion/5
        public void Put(int id, [FromBody]string value)
        {
        }

        // DELETE: api/Conexion/5
        public void Delete(int id)
        {
        }
        SqlConnection miConexion = new SqlConnection("data source = snare.arvixe.com; initial catalog=****; user id=****; password=****");
        [HttpPost, HttpGet]
        public string DatosEmpresa(int idempresa)
        {
            try
            {
                if (miConexion.State == ConnectionState.Closed)
                {
                    miConexion.Open();
                }
                SqlCommand comando = new SqlCommand("SELECT idEmpresa, [Status], Empresa, RFC, svrFacturador, usrFacturador, bddFacturador, pwdFacturador, cuantosFolios, comunFac, llave FROM logins where idEmpresa = '" + idempresa + "'", miConexion);
                comando.ExecuteNonQuery();
                Conexion datos = new Datos.Conexion();
                DataSet ds = new DataSet();
                List<Conexion> LstRazon = new List<Datos.Conexion>();
                SqlDataAdapter da = new SqlDataAdapter(comando);
                da.Fill(ds, "logins");
                //da.Fill(ds, "CrmCustomersEmails");
                //Data Row llenarlo con el data set 
                DataRow DR;
                DR = ds.Tables["logins"].Rows[0];
                //Si el usuario existe, extrae sus datos
                if ((idempresa == int.Parse(DR["idEmpresa"].ToString())))
                {
                    SqlDataReader reader = comando.ExecuteReader();
                    if (reader.Read())
                    {
                        //Traer los datos del usuario logueado
                        datos.Status = int.Parse(reader["Status"].ToString());
                        datos.Empresa = reader["Empresa"].ToString();
                        datos.RFC = reader["RFC"].ToString();
                        datos.svrFacturador = (reader["svrFacturador"].ToString());
                        datos.usrFacturador = (reader["usrFacturador"].ToString());
                        datos.bddFacturador = (reader["bddFacturador"].ToString());
                        datos.CuantosFolios = int.Parse(reader["cuantosFolios"].ToString());
                        datos.ComunFac = (reader["comunFac"].ToString());
                        datos.IdEmpresa = int.Parse(reader["idEmpresa"].ToString());
                        datos.llave = Guid.Parse((reader["llave"].ToString()));
                        LstRazon.Add(datos);
                    }
                    miConexion.Close();
                    var JsonLogin = JsonConvert.SerializeObject(LstRazon);
                    return JsonLogin;
                }
                else
                {
                    miConexion.Close();
                    return null;
                }
            }
            catch (Exception ex)
            {
                miConexion.Close();
                return "Error" + ex.Message;
            }
        }
    }
}

and this one my RouteConfig file

public class RouteConfig
    {
        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

            routes.MapRoute(
                name: "Default",
                url: "api/{controller}/{action}/{id}",
                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
            );
        }
    }