Account Set Up Went Bad

I signed up for Xfinity's 1 Gig internet plan and that set up went fine.  As part of a promotion, I am able to get one mobile line for free for one year (as long as I have the internet service).  I checked and I was able to port over my iPhone 15 pro.  But, instead of setting my up on an unlimited line, they set me up on a pay by the gig line.  I called the next day to get that fixed and they said I would need a separate, temporary phone number so they could move my number to an unlimited line.  Since then (about a week ago), I've had two lines on my account.  I don't want two lines and I don't intend to pay for two lines.  I've used Xfinity Assistant several times and have been connected with associates.  I've also called twice.  Each time they say they will fix the issue, but it has yet to be resolved.  I still have two phones on my account (only want one) and, even worse, I see two set up charges - one for a phone I never had nor wanted!  My fear is this never gets resolved and they try to charge me for a phone service that was supposed to be entirely free for a year.  Has anyone had actual success getting something fixed?