fēnix 3 HR Display issue

Hi! I have a problem with my fēnix 3 HR. Yesterday a bright line shaped spot appeared on the display, which would not change its position when the screen image changes, and is even visible when the device is in power off state. It looks like a scratch below the glass or something, dead pixels / blind spot..

Please, have a look at the pictures I've made:

Today I observed that the dead region is actually growing..

What can I do? Is it possible to repair this somehow? Thanks for your help.

P.S. I know this is the fēnix 5 forum; however I guess what I'm describing could happen with that device as well.