hi chillerman, possibly going to wage war....

my mistral fridge freezer - the fridge is at +22. The freezer has came from -21 to -8. Both now are +22.

Having had the panel off the freezer I have concluded:
The fan in the freezer spins freely when the fridge door is closed, however the air does not reach the fridge. I checked by faking the door closed and putting my hand over the vent - no air.
The radiator blades in the freezer are frozen over. I just defrosted it recently due to this problem with worked temporarily but now its doing it again. I never had the insulated bit off before so now i guess it will do it a bit quicker, while I look for an answer.
I have whipped out the yellow thermistor as everyone keeps banging on about and it makes no difference, to me that's just a temperature sensor, cuz when you take it out, the unit cant read the freezer temp.

I am not an engineer, but i'm not a dummy either. I can wield big and small tools, to top it off, im a 3 to 4 spanner Haynes guy, lol....

In my completely untrained opinion its not defrosting properly/at all, in conjunction with the air not blowing into the fridge to cool it, and dam, I really wanted cheese on toast today and the cheese is like rubber this morning

What plans of diagnosis/elimination should I take?

thanks in advance