Firebase httpsCallable returns error from React Native

Question

So when I open functions in my firebase console. I open the function's link which is https://us-central1-geochatterthing.cloudfunctions.net/getWall . And this link gets opened into a browser with below error

{"error":{"status":"INVALID_ARGUMENT","message":"Bad Request"}}

Also, my scenario is that there is an app already on Google Play on which images are being fetched using the function getWall. And now I'm supposed to redesign the app using the same original code.

But now the getWallfunction doesn't seems to work.

const wallFunc = firebase.functions().httpsCallable('getWall');

result = await wallFunc({size: 15});

Can someone please tell me what could be the issue here? Thanks in advance! :)

UPDATE:

Below is the code for the getWall function I accessed from Google Cloud Console.

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _messages = require("./messages");

Object.keys(_messages).forEach(function (key) {
  if (key === "default" || key === "__esModule") return;
  Object.defineProperty(exports, key, {
    enumerable: true,
    get: function () {
      return _messages[key];
    }
  });
});

var _conversations = require("./conversations");

Object.keys(_conversations).forEach(function (key) {
  if (key === "default" || key === "__esModule") return;
  Object.defineProperty(exports, key, {
    enumerable: true,
    get: function () {
      return _conversations[key];
    }
  });
});

var _profiles = require("./profiles");

Object.keys(_profiles).forEach(function (key) {
  if (key === "default" || key === "__esModule") return;
  Object.defineProperty(exports, key, {
    enumerable: true,
    get: function () {
      return _profiles[key];
    }
  });
});

var _auth = require("./auth");

Object.keys(_auth).forEach(function (key) {
  if (key === "default" || key === "__esModule") return;
  Object.defineProperty(exports, key, {
    enumerable: true,
    get: function () {
      return _auth[key];
    }
  });
});

var _apiHttp = require("./api-http");

Object.keys(_apiHttp).forEach(function (key) {
  if (key === "default" || key === "__esModule") return;
  Object.defineProperty(exports, key, {
    enumerable: true,
    get: function () {
      return _apiHttp[key];
    }
  });
});

var _friends = require("./friends");

Object.keys(_friends).forEach(function (key) {
  if (key === "default" || key === "__esModule") return;
  Object.defineProperty(exports, key, {
    enumerable: true,
    get: function () {
      return _friends[key];
    }
  });
});

var _wall = require("./wall");

Object.keys(_wall).forEach(function (key) {
  if (key === "default" || key === "__esModule") return;
  Object.defineProperty(exports, key, {
    enumerable: true,
    get: function () {
      return _wall[key];
    }
  });
});