Marq - Parts not replace even though under warranty

Complaint lodge with marq regarding low cooling and technician visited and charged visit fees, and suggested to change compressor which is under warranty as five years were not over from purchase. Technician promised that within *-* days problem will be solved. However technician thereafter not visited and after about ** days mail received from the company part cannot be replaced as technician reported that gas filling done from other non brand technician.