If you have no chilling, then follow this process before arranging technician.

-Check that all normal things are going (inner fan, rear fan, compressor, controller)
-Check for error on the LED display
HHH showing on display (Flashing) means inner temp has reached higher than maximum allowed HIGH set point OR if cabinet sensor is short circuit
LLL showing on display (Flashing) means inner temp has reached lower than maximum allowed LOW set point OR if cabinet sensor is short circuit
*Either of these errors cause alarm also, this can be stopped by pressing any button