Hello i am in need of a GHL member/supervisor

I live in the Netherland and a have bought a GHL doser 2 in Oktober from a german online shop and all went well.
Everyday it did the job and i was very happy with the unit.
I have a iPhone X and i login with a macbook still no problems.

This morning i woke up and looked at the tank and a heard the doser dosing.
But after a few seconds i realise that the doser does not stop.
I open the cabinet and i was looking to a empty KH+ bottle and the pump kept running.
Opened the app to stop the pump but no reaction wheel was spinning in the app
I looked at the settings in the app and all settings are changed to 60.000+ dossing's and also the quantity was changed.
The unit worked for weeks with no adjustments from me so the unit changed the setting by itself !!!
Please help and advice what to do because i don't trust it anymore and want to know what happend and how to avoid this.
i had some luck that my KH was 7,9 and only a quarter left in the bottle KH+ so it went empty in the night and run dry now my tank is 9,9
But this could kill my tank in a future malfunction
Please help Best Regards Remy