Drops the Cloud connection - irritating!

Had this problem Before and solved for a couple of weeks. Now again. After restarting the My Cloud unit it works for 2 - 3 hours and then drops the remote online Connection. Continous working inside the router. But no internet Connection.
Have a dedicated ip for my Cloud and setted DHTML.
How can I set up a reliable Connection ???

I would look at these KB Articles below and see if they help.