Simple Website into an Web App

Iam new to kotlin and trying to convert our website into an webapp, the problem which iam facing is - my webapp is only showing the loading gif of our website but not loading the website. although the code is working fine on other websites. Kindly help me fix it.

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>

<androidx.constraintlayout.widget.ConstraintLayout xmlns:android=“http://schemas.android.com/apk/res/android
xmlns:app=“http://schemas.android.com/apk/res-auto
xmlns:tools=“http://schemas.android.com/tools
android:layout_width=“match_parent”
android:layout_height=“match_parent”
tools:context=".MainActivity">

<WebView
    android:id="@+id/webview"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_marginBottom="4dp"
    app:layout_constraintBottom_toBottomOf="parent"
    tools:layout_editor_absoluteX="-3dp" />

</androidx.constraintlayout.widget.ConstraintLayout>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<uses-permission android:name="android.permission.INTERNET"/>

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

MainActivity.kt

package com.example.webapp

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.webkit.WebResourceRequest
import android.webkit.WebView
import android.webkit.WebViewClient

class MainActivity : AppCompatActivity() {

var mywebview: WebView? = null

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    mywebview = findViewById<WebView>(R.id.webview)
    mywebview!!.webViewClient = object : WebViewClient(){
        override fun shouldOverrideUrlLoading(view: WebView?, url: String?): Boolean {
            view?.loadUrl(url)
            return true    }
        }
    mywebview!!.loadUrl("https://www.epremy.com")
    }
}