Vivomove Style Frozen. Anyone an idea how to reset?

Unfortunately my Style stop working. The hands are on 12:00. At first the HR lights were on. I tried to connect it to the chrager to get it working. In stead, the HR light went off and never went on again.

I can’t connect to the phone, I can’t connect tot Garmin Express. It seems completely dead. 

The manual describes how to reset the watch using the software, but that is not an option right now as I can’t connect to the software. There seems to be a little pinhole at the back, but it doesn’t seem to be a reset button.

Anyone ideas? I’m afraid I have so sent it back otherwise...