Hotpoint fridge freezer FF200e

[imigix]

This unit is about 15 months old, in the last few weeks the freezer has been iceing up under the bottom storage box on the plastic lineing.

I have tried turning the control down to min but no improvement, before this it was at half way.

I have bought a thermometer and placed it in the bottom box and even at min control setting it reads -20.

Any ideas please.

 

[rocks1]

drain hole blocked try total defrost for 24 hrs