Trying to file a grievance

Was talked down to. Brought  to tears because a bill was prorated and sent late after a move. At the same time my rate changed.  Multiple  CS agents telling me different answers to how I got a balance from June on a bill statement of $115. After auto pay paid 106.70 June 4. Bill for July stated 171.13. Called to see why it jumped 106 to 171. 1st customer service said new billing cycle to end of month and was pro rated because of move. . Then bill came saying i owed 115 bill from June +169.97 for August 287.20. Kept calling in August  to see where this 115 came from. Got lied to and the run around. One CS said they found the problem put in a special ticket and a new promotion. And if bill didn't  change by then to called. I did. Got talked down like I didn't pay my bill before  I moved. And need to pay my bill. Yet they were on auto pay I paid always. Instead of being helped I was treated like I don't pay my bills. Couldn't pull up my old statements because  they closed it opened a new one when I moved. Yet was told I can see last 24 months of statements. Went into store. Same over talked Yet was helped with the peacock bill. That came from Xfinity but told no we don't charge for it. But Yet there was the message from Xfinity saying activate peacock.  Had to pay 79 for something that was to be free. I had to call peacock because Xfinity CS said they couldn't help me with that. Though it was there email. Made payment on 25th of 161 Yet told still owed 252. So frommid June to end of this month 413.57. With no peacock after CS special ticket changed plan then it gets denied. But peacock service wasn't.  Then trying to get clarity as if a bill for 115 was sent before I paid the 171. June email July email all say 171... no 115. But I'm talked to like I'm not trying to pay. Something I've paid for for over 5 yrs. Paid a total  of 723.50 from Jan to Jun.  July August and September costing me over 699 with disrespect. Noone answered my questions on the calls but asked me to wait while they tried to fix what I've been talked to about  for 2 months. I got no answers just told you didn't pay your bill so you owe pay your bill. No one listed but quick to put someone down. I couldn't even get the answer to "how to file a complaint" until after  once again being told... you owe June... you  didn't pay it... you have to pay that's why it's there. HORRIBLE SERVICE EXPERIENCE... I've done customer service; agent and management for over 40 yrs, and they brought me to tears over the phone. For a bill that cam after I paid a bill and given wrong explanation and information.  To be made as if it's my fault I don't pay my bills. I'm done with Xfinity/comcast. I just need information on how to file a complaint finished this extreme overpayment and end my service.