Call the Technician and he established the defrosting board and its thermister needs replacement.
He ordered via his sources and we did not get it for 3 weeks.
Then I took the matters under my control and called the manufacturer.
The two parts we needed were not available and were special order and on the top prices were higher than YOURS!
So I found you guys and went on line and found the correct parts and better price and items were in stock!
Got the parts with next day delivery.
Called my technician who installed it.
Job done.
I told my contractor get parts from you in future and gave him copy of my order for his record.