Keeps running else statement even though it shouldn't

So I wrote some code to use as a Log In system in my 2D game. But whenever the button is clicked upon, the else statement that shouldn't be triggered triggers. I later found out it was because the strings the if statement compared weren't filled in the first time when clicking. So I added some sort of loop. This doesn't work for some reason and I have no idea why. If anyone knows how I could fix this please tell me. Thanks in advance.

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.UI;
 using UnityEngine.SceneManagement;

 public class Login : MonoBehaviour
 {

 public string databaseUsername;
 public string databasePassword;
 public Button Continue;
 public InputField Username;
 public InputField Password;
 public string inputPassword;

 private int Teller = 0;

 string LoginUrl = "localhost:8080/Logingegevens.php";

 // Use this for initialization
 void Start()
 {
     //functie oproepen als er op aangegeven knop gedrukt wordt.
     Button btn = Continue.GetComponent<Button>();
     btn.onClick.AddListener(TaskOnClick);
 }

 public IEnumerator Loggingin(string Username)
 {
     WWWForm form = new WWWForm();
     form.AddField("inlogusernamePost", Username);
     WWW www = new WWW(LoginUrl, form);
     yield return www;
     databasePassword = www.text;
 }

 // functie van button 
 void TaskOnClick()
 {
     StartCoroutine(Loggingin(Username.text));
 
     if (Password.text == databasePassword)
     {   
         SceneManager.LoadScene("PROTOTYPE");
     } else {
         if (Teller == 0)
         {
             Teller++;
             TaskOnClick();
         } else
         {
             SceneManager.LoadScene("Log in");
         }
     }
 }
 }