"There is an issue with the device connectivity. Please restart the GUI"

I have this message... Yesterday ever ting was fine. Could read motor voltage and spin up the motor. Control via I2C.
Also save the MPET values.

Board runs without the software.

But when I try to reconnect ( want to change the values)
It lights green and connected.

But as soon as I press a button.

Or reset the device i'm in an endless loop.

Tried it with Firefox, Chrome also on a other PC... allays the same.

Any idear?