Smeg fridge freezer temperature high

[Grenage]

Model FAB30QRO.

The freeze (unadjustable) is around
-15 to -17; the fridge is 10-12. Adjusting the temperature dial does very little.

I've done a full defrost; the unit has no vents or fans. I assume there's no coolant leak or it wouldn't be working at all. Could anyone suggest things I could check?

I'd sooner bin it, but the other half is fond of this piece of crap.

 

[jj4091]

Fridge door Seall leaking?

 

[Grenage]

Not that I can tell, I can't see or feel any cold air escaping.