Beer fridge having inconsistent temperature through out?

We have acquired this beer fridge from 2nd hand. Temperature looks OK on the built in display but when we measure (see picture) the right and middle hand side are around 3-4 degrees. But the left hand side is at around 7-8 degrees. I wonder how this even possible in one single fridge... Does it makes sense? I checked visually the compressor, slightly warm to the touch, coil seems clean. 2 ventilators inside the fridge are running regularly and normally. And it feels odd that 2/3 of the fridge is at the right temperature. Any ideas on how to fix that? NB: it's a polar GL013-06 submitted by /u/ResistInternational7 [link] [comments]