When YouTube keep saying no connection it can be caused by your internet being down, your WiFi being slow or your Youtube App on your device such as our android phone or tablet may need to be reloaded or reinstalled.
Sometimes my Youtube app will need updated or reinstalled and sometimes I need to restart the android phone or android tablet to get the Youtube App to load.
If regular Youtube loads on your computer or browser but not on the Youtube App then it's either a bad connection to your device or the YouTube app needs reinstalled or updated.
Sometimes just restarting your device helps with the issue.
If not then it could be just YouTube not working properly and then in that case they need to fix it.
But most times it's a problem with your internet connection or YouTube App.