Ionic cordova button not clickable in IOS Emulator -- Need Help

When I run the below code on a browser; it works like fine and when I click the buttons they trigger the functions, but when I deploy it on ios emulator then the click does not work at all. This is on ionic 5.


<ion-content padding>
      <ion-button expand="block" (click)="triggerThis()">Add Developer Info</ion-button>
      <ion-button expand="block" (click)="gotoNextPage()">Goto Next Page</ion-button>


import { DatabaseService, Dev } from './../../services/database.service';
import { Component, OnInit } from '@angular/core';
import { Observable } from 'rxjs';
import {AlertController} from '@ionic/angular';
import {NavController} from '@ionic/angular';
import { Router } from '@angular/router';

  selector: 'app-test-template',
  templateUrl: './',
  styleUrls: ['./'],
export class DevelopersPage implements OnInit {

  // tslint:disable-next-line:ban-types
  changevar: String = '<<<<<<<>>>>>>>>';

  constructor(private db: DatabaseService, private alertController: AlertController, private route: Router) { }

  gotoNextPage() {

  triggerThis() {

    this.changevar = 'This is a message set easily ';



  async openAlertBox() {
    const openAlertVar = await this.alertController.create({
      header: 'Insert your text',
      message: 'enter your text' ,
      buttons: [{
        text: 'Cancel'
          text: 'OK'
      // tslint:disable-next-line:no-shadowed-variable

    await openAlertVar.present();