Customer Service Concerns

Hello,

I had some internet service issues not to long ago. I spoke to tech support. They scheduled at on-site tech visit to my home, beacuse of the service issues I've experience in those 2 weeks. Xfinity agent stated I would not get charged.The technician arrive and replace the xfinity modem. Technician stated that the modem was overheating, anf that was why it was malfunctioning. Technician also stated there no charge. However I received a $100 invoice for the technician. I called customer service explained  the issue. He said sorry I can not remove the charges. I asked to speak to his supervisor. Supervisor stated I would get the $100 charge waived. Even made an escalation, ticket. However after conversation I received an text from xfinity stating that my escalation ticket was denied. I've had 1 to many service visit in my home. Never been charged beacsue of equipment issues. I'm trying to get a hold of someone that can actually help me.

Thanks 

K