Side mirrors stopped auto dimming - what to check for?

Basically what the title says. I have a 2015 Octavia Mk3 TDI. I noticed recently that my side mirrors have stopped dimming. The rearview mirror dims perfectly but the side mirrors don't. All the other functions of the side mirrors seem to be working. 

I had gotten a full service done at a non-dealer workshop and they reset the service timer. Not sure if that reset some code because I didn't check if this happened since then. 

Previously, once when I got a car wash done, the mirrors had stopped dimming and then in a few hours, automatically started working again. 

Doesn't seem to be the fuse because the rearview mirror seems to be dimming. 

Anybody have any idea where I can start looking? Or know the code to get them dimming again?

Thanks in advance.