The worst customer service ever! Requested for gen...

The worst customer service ever! Requested for general servicing of our built-in ovens (we have 3 units in our school). The technician came, turned on all 3 ovens at highest setting, waited for half an hour for it to heat up, then said "your ovens look fine leh. Nothing wrong". We had already informed the Hotline officer when making the appt that the though the ovens were working, there was inconsistent performance and some hot spots. Hello, we don't need to pay you $95 per oven just to turn it on (and waste our electricity) and just declare it is fine. When asked about any tools, probes or thermometers he could use to check the heating elements, he said he didnt bring it because it was taken by the other technicians!? How is it logical that the very thing needed to test an oven's heating element was not even brought in the first place? Stop ripping off your customers!