Incorrect information given to me regarding my bill

I recently changed my service package due to financial issues.  I could no longer afford $110 per month for cable while on retirement.  The agent that helped me over the phone created another package with just internet and streaming package for a total of $72 per month.  My payment that was to be drafted out of my bank on the 6th of the month was to be the prorated amount of $96.50.  This was a very important monthly reduction for me in November of $82.  I was assured that this would be the payment not only by this agent but also one in the Sugarland TX store location and once again with someone on the chat line.  Well that didn't happen instead $178 which was the original payment was taken out.  $82 might not seem like a large amount to some but to me on a very limited budget it was a disaster.    It really put me in a bind trying to cover bills.  But what is the most aggravating thing is that with me supposedly being a Loyal member nobody gave a flip.  A refund was requested three times and denied three times and I was told I wouldn't have to pay anything the next month since I had a credit.  The credit for December doesn't help with November bills.  As long as I have been with Xfinity this really upsets me.  I will now try to locate a different internet provider (not that anyone at Xfinity will care).  Someone needs to retrain the employees not to give out false information.