Unresponsive Comcast Representatives, Incorrect Equipment, & Overcharging

TLDR: Comcast is overcharging us for incorrect equipment that we sent back, and I cannot get a resolution or response. I sent a DM, and I am hoping that helps, but if anyone knows an effective way to escalate an issue for assistance, any advice would be appreciated.

I have been attempting to resolve an issue with Comcast since JULY. Upon requesting assistance with acquiring access points for internet at our small business, we were incorrectly given residential extenders. Fortunately this was caught by myself prior to processing and shipping the order, but despite multiple communication attempts to cancel the extenders, our only response was a confirmation that they were processed and shipped. A technician came to our business to help set up our fax machine and verified firsthand that these extenders are for residential use and not appropriate for the needs that we communicated. We were told by the technician and customer support via email that we should return the extenders by bringing them to a UPS store. Upon trying to gain confirmation that the extenders were received and the cost would be removed from our account, we were told that there would be a thorough review of our account and corrections would be made. We did not receive follow up. I reached out again. Again, we were ignored. Now we have been charged for THREE MONTHS for incorrect extenders that we requested to not be sent in the first place.

Additionally, $220 for FOUR DAYS in June is exploitative. When I spoke with a representative over chat, they made it sound like there would be a credit for our first month to appropriately prorate their services, but it has been months and this has not been done after several emailed requests. My question is: Does anyone know how to get in touch with someone who is actually able to credit our account and rectify the situation?