Help with mobile bill issue

I have tried calling and using online chat resolve an issue but have had no luck! I have called three times. First call the rep told me the issue was caused by xfinity rep doing something incorrectly and it would be escalated. It’s been a month and it hasn’t been corrected. I called back and was told it would be fixed by end of day. Nothing! Tried using chat and that rep told me it wouldn’t be fixed and he do a callback but the call received was for internet billing, they transferred me to mobile billing, who then transferred me to sales! How can I get to someone that can actually help me!