Need IMEI whitelisted

I bought a Ulefone mini 20t pro after calling Xfinity and making sure that the phone could be whitelisted if there were "compatibility" issues as I have read people having in the past, especially with Verizon. 

I bought the phone and tried to get service transfer to it. I'm being told that there is no way to whitelist the IMEI as per Xfinity policy when I finally escalated it to the escalation team, which probably told me to go to a different carrier and that the conversation was over and I was hung up on. 

I would really like to use the brand new phone that I bought on this network, I know it is physically compatible with the network, I just need somebody to make the policy decision to add the IMEI so that I can remain a customer with Xfinity