MMS on Xfinity Mobile while connected to wifi6

I just got a new netgear router.  Both NetGear and Xfinity claimed that the router is compatible with xfinity.

My family uses android, and this problem impacts all of us, not just one phone.

There is a very specific scenario that does not work.

If my phone is connected to my wifi6 network, then I cannot send or receive group messages that are MMS

I called Xfinity mobile, and they said since the phone works when I'm NOT on wifi, then it's an internet problem and they sent me to internet support

Internet support said since my phone was the only device having an issue, then it's a mobile issue, not internet related.  So they sent me back to mobile.

Back on mobile, they said it's a router problem.... call NetGear

NetGear said that everything else works on the router besides the phone... Must be a phone issue.

There must be a compatibility issue with wifi6 and MMS and xfinity

Right now, my workaround is to make sure my wifi is turned off on my phone when I am at my home, so that I don't risk not receiving group texts.

This is not a sustainable solution

Thanks