Youtube fullscreen button not working using Youtube API

I am using Youtube API for loading youtube videos in webview for Android. Everything is working fine but the click event for full screen is not triggered.

Below is my code:

private fun getHTMLData(videoId: String): String {
        return """
        <!DOCTYPE html>
        <html>
            <body style="margin:0px;padding:0px;">
                <div id="player"></div>
                
                <script src="https://www.youtube.com/iframe_api"></script>
                <script>
                    var player;
                    function onYouTubeIframeAPIReady() {
                    
                       console.error("-------playing-------");
                        player = new YT.Player('player', {
                       
                            width: '100%',
                            videoId: '$videoId',
                            playerVars: {
                                'playsinline': 1,
                                'allowfullscreen': 1 // Enable fullscreen mode
                            },
                            events: {
                                'onReady': onPlayerReady,
                                'onStateChange': onPlayerStateChange
                            }
                        });
                        
                        // Call updateHeight function on initial load
                        updateHeight();
                       
                    }
                    
                    function onPlayerReady(event) {
                       console.error("-------onPlayerReady-------");
                        event.target.playVideo();
                        
                        // Attach click event listener to the full-screen button
                     var fullScreenButton = document.querySelector(".ytp-fullscreen-button");
                     if(fullScreenButton){
                     fullScreenButton.addEventListener('click', function() {
                       toggleFullScreen();
                     });
                     }else{
                      console.error("-------Fullscreen button not found-------");
                     }
                     
                    }


                    function onPlayerStateChange(event) {
                        // Handle player state changes here if needed
                       
                    }

                    function toggleFullScreen() {
                    
                        console.error("Toggling fullscreen");
                        if (player.isFullscreen()) {
                            player.exitFullscreen();
                        } else {
                            player.playVideo(); // Autoplay is required for full-screen on mobile devices
                            player.getIframe().requestFullscreen();
                        }
                    }
                    
                  
                    function updateHeight() {
                        var screenHeight = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight;
                        document.getElementById('player').style.height = (screenHeight) + 'px';
                    }
                </script>
               
            </body>
        </html>
    """.trimIndent()
    }

I am loading this in webview as :

 webView.apply {
            settings.javaScriptEnabled = true
            settings.loadWithOverviewMode = true
        }

        webView.webChromeClient = object : WebChromeClient() {
            override fun onConsoleMessage(consoleMessage: ConsoleMessage): Boolean {
                Log.e("WebView------------->>>", consoleMessage.message())
                return true
            }
        }

        val htmlData =
            getHTMLData(id)
        webView.loadData(htmlData, "text/html", "utf-8");

I am getting error log that is inside the else block console.error("-------Fullscreen button not found-------");

Am i missing something?