Beko DSC85W problem

Hi. I’ve had my Beko for years without an issue but now I need some advice. The other day it stopped mid program because the water tank was full, no problem there. But since I’ve emptied the tank the dryer will no longer heat clothing or spin properly.
If I restart the program it goes into a loop of spinning slowly clockwise for 20 seconds, pauses for 5 seconds, spins slowly anti-clockwise for 20 seconds etc. There is no heat.

I’ve cleaned it all the way through (filters, sensors, water pump, condensor etc) but still nothing. Trip button on the heater was normal and still down.

Any suggestions as to what would cause this? Would changing the heater unit on the back fix this?

Thanks
Andrew