Crash energy saving


I was about to change some settings in energy saving mode, suddendly the watch crashed.

Now everytime i want to enter the same menu again to set anything the watch crashes.

Furthermore everytime i want to activate the energy save mode(press and hold "light button") since then the watch crashes.

Other menues work perfectly fine, so far.

What can i do? Is it wise to update to 16.10 beta or is it better to restore to default settings? And are the settings going to be restored afterwards? 

Steps i remember:

OS version 15.20, 35% battery

Activated/Deactivated energy saving mode a few times

Changed settings "when sleeping" and "backgroundlight" a few times

When i changed the backgroundlight to "no change" the watch crashed and i saw the blue triangle Logo. OnButtonPressed returned a beep.