DEFY technical and customer service is unacceptable

I have had 2 Defy technicians in almost a year look at a problem with my freezer and advise it they do not know what is wrong. Both asked for payment in cash. The second technician who came through about 2 months ago advised a report can be provided on the unit for insurance purposes and asked for cash to get a report immediately. I declined and asked to be invoiced (merely for looking at the model no. of unit only, no work done) but to-date calls and messages to Defy are not forth coming. The first technician, from about a year back, increased the temperature for cooling of the freezer and topped up the gas, which he said was not required but could resolve the problem which still persists to-date. Thereafter when the problem persisted he ignored calls and messages. Please beware when purchasing Defy Appliances - their technical and customer service is unacceptable!