Can I cancel the mobile plan before phone is activated?

I have had Comcast/Xfinity at the same address for over 30 years. Currently we just have Xfinity Internet, never had Xfinity Mobile. When I called Xfinity to get a cheaper and faster Internet service promotion was told I qualified for a free Xfinity Mobile line. It seemed like a good deal, so I said yes.

I tried to activate my iPhone (which was purchased directly through Apple) in order to take advantage of the free 1 year Xfinity mobile offer. The activation process through the Xfinity App never worked. After several frustrating hours trying to activate my phone, I gave up and told the CSR to cancel the Xfinity mobile. My husband added me back to his account on a different cell carrier.

Three days later I was called a different CSR because my mobile activation had not gone through. Each time I told the CSR I wanted the mobile account cancelled. A different person told me the account was deactivated and I would get an email confirming the deactivation. I never got an email

Today I was called by a CSR who wanted to help me get my phone activated. I told them I wanted the Xfinity mobile account to be cancelled. After being escalated to a different person, I spent an hour on hold and finally got this notification on my phone: "Finish Cellular Setup - an eSim from Xfinity Mobile is ready to be set up on this iPhone".

The CSR told me they couldn't cancel a mobile line that had never been activated, so they created another phone number for my line. According to this person they will be able to cancel the mobile line after activating a new number on my phone. I am currently waiting for a call back to confirm this.

I am unwilling to change the number on my phone. Is it true that Xfinity can't cancel a mobile line if it has never been activated?