changing account information

Xfinity will not let me add my phone number because it is associated with my other / old / different account, but Xfinity wants a second authorizaton; so stupid.  I moved and the old account has my current phone number.  There is no reason a transfer of service should remove the ability to transfer phone number, too.  My phone is NOT XFINITY.  This entire transfer of service has been a nightmare.  Five hours of online chat, disconnects from Xfinity people; I told them the problem was at their end and it was.  Finally, someone with a brain called me back to devote 5 minutes to activating my new Internet.  Was this a game??  Why would it take 5 hours of online chat when a phone call resolved it in 5 minutes?  Online chat is a waste of time for everyone.