Over charged, rebate never offered, "Take $20 and be quiet"

I have changed my service levels, dropped comcast TV service and I am now being billed $60 a billing period, instead of $160 per period. The reason this change was asked for was that for the past six  previous billing periods, I was charged for internet service for a 200+ Mbps download level but  received only 20 to 100 Mbps which is much less then what I paid for. After being given many excuses why, or delayed an answer, or given excuses that comcast was doing service work in my zip code. The download speed did not return to previous levels, this issue has gone on for six months+. During this back and forth I now know that comcast, can easily examine my usage and received download speed with their equipment. I was also told by comcast techs, on the phone, that yes, there was a drop in download speeds, starting in May 2023, which continued till I changed my service on Oct 10, 2023. Your Rotunda office and by your comcast phone service techs, on previous occasions, explained to me, that comcast would "accurately prorate", my future bill to show what the actual download speeds were and what speed I really received, from 5/23 till 10/9/23, when I reduced service. I have noticed that my new comcast statement, does not reflect (any) refunds/rebates, concerning the promised adjustments for undelivered internet service, for the previous billing periods from May through Oct/Nov of 2023 and now this new one for Nov/Dec 2023. I would like to know when comcast, will bring my account up to date, concerning this reoccurring charge for the past six months +. With great efficiency comcast makes sure that their bookkeeping is accurate. Now, I see that correcting a comcast billing issue that costs me money, that comcast is not as diligent. What I am seeing, is comcast not being as diligent or as interested in, is that when I am charged for undelivered comcast services.  It is not as interested in making sure that I am correctly rebated, for the services not delivered but charged for.  As well known, comcast has perfected the distractions, confusion, re-sign ins of many support numbers and dropped calls, for billing corrections,  or the now, given promises of call backs, never made or quick to say billing answer of  "We'll give your $20 as a courtesy", even when the amount over charged may be much larger then their offer of $20. Typical comcast standard operating procedures, when their able to operate as the monopoly cable service, in the Baltimore MD area. I demand the same accuracy that comcast uses for billing customers, for when comcast may have to correct, rebate or reimburse that same customer, when the error resides with Comcast

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