HELP: Blynk says "Arduino UNO is offline."

I created a new project which I found here: I changed my auth token and everything, and when i run the sketch it goes fine. However I can’t seem to connect my Blynk app to Arduino, as what my mobile app says (“Arduino UNO is offline.”). My serial monitor, however, keeps on displaying this:

Do you know what’s wrong and how I can fix it?

I tried running telnet 8442 but what appeared was

Look like your firewall blocking connection or router has blocked 8442 port. You have to fix that.

@Dmitriyhow can i unblock it??

It depends on your router. Usually you can reach router page with IP.