[HELP] Ardruino UNO is offline

Hi guys. I’m starting learn with Blynk and my first example is turn on and off the LED and it was working. But when I use the example PushData, the compiler is done but app says Ardruino is offline. Please help me.

Need much more information. Confirm if using cloud server, your method of connecting UNO to server, and post the code you are having issues with (properly formatted please).