Edge 830 unusable, touchscreen unresponsive, help ASAP

I did not find any similar case of a problem on the internet...

My touchscreen stopped responding on bottom half of the screen, only upper part works, but it is unusable like that, I cannot go to, courses, training, cannot click bottom "buttons" home back etc so any menu/option I go in I cannot go back. Cannot enter different crank length or calibrate powermeter and cannot turn device off (only way is holding power button). And now is the peak of the season and races, I need working unit as soon as possible. I cannot just buy another one, it is way too expensive for something of poor quality like this, I payed a lot for this one and it is just two years old... I hope it can be fixed somehow.

Does anybody knows is it anything that can be done?

I did not try hard reset yet because if it does not helo, I will lose all settings and even this little functionality. Now I can only swipe screens left right, use lap button and save ride.

I suspect some calibration issue because my lcd got unglued from the case, water got between glass and black emulsion (bad quality). It is not bad display, I have three different new LCDs and bottom half of touchscreen does not work on all of them.

Also, I don't know if hard reset would help. Or reflashing firmware, and how to do that. Or if it is possible to manually flash older firmware, I would prefer that (and not latest "fixes" which make devices worse and slower) but cannot find old files. I backed up my personal settings and stuff.

Can I get some support from Garmin and where? I will look for some contact form.

Need any help I can get. Thanks