Airtel - Airtel WiFi technician behavior

I had an issue with my Wi-Fi on December *th and I filed a complaint. I was informed that a technician will call and guide me on the issue and resolve it. The technicians showed up late in the evening and started being disrespectful and rude towards my mother. The way they spoke was unacceptable and it cannot be tolerated. The number that I received a call from the technician was +**-**********. I gave a compliant against the technician by calling airtel customer care escalation department but there is no proper response. The supervisors keep giving false information and disconnects my calls. I request you to please take necessary action against the technicians who were extremely rude and yelled at my mother.