Ionic HTTP returning different response on Android

I’m making a HTTP Get call to my API. My POST works fine and returns the correct response body.
When I run as Ionic Serve, my GET also returns the correct body with the object, but when I run the app as Ionic Cordova Run Android my GET resturns me my index.html as a response body.

I can’t make it work, can anybody help me, please?

This is my GET

import { Http, RequestOptions, Headers } from '@angular/http';

async getPersonByFilter(filter) {

    return new Promise((resolve, reject) => {

      let headers = new Headers();
      headers.append('Authorization', ' Bearer ' + this.userToken.access_token);
      let options = new RequestOptions({ headers: headers }); 

      let baseURL = "/api";

      this.http.get(baseURL + '/Person?Filter=' + filter, options)
        .subscribe(res => {
"res: " + res)
        }, (err) => {
          console.log("Not working: " + err)

This is the response when I run on Android