WiFi Calling Oneplus 13

Hi - I have tried to enable WiFi calling on my OnePlus, but I don't think it's working correctly.

I have seen other posts and they mention about the device needs to be supported on Vodafone, if this is the case, what is the process to request it?

I'm coming from 3 and it worked without issue on that network.

Thank you

Think I have sorted it, was looking in the wrong place!