On unlimited premium plan, international roaming is not working

I am on unlimited premium plan. International roaming does not work in India (or even germany). I have tried many things. Roaming is on. I get the 4 bars with "R" symbol next to it indicating that roaming signal should work. Please help. I have a google pixel 6a phone.

(folks go with a more reliable network not xfinity if international roaming is important to you).