Calls not working on MacBook Pro with iPhone 15

Hi, I used to take and make calls from my MacBook, connected to my iPhone via the same WIFI.

But for some time now, I haven't managed and always get the same error :

Even though they are in the same network - literally on the phone's hotspot:

The iPhone is new - iPhone 15 bought this month.

In the past, I sometimes swiched eSIM (I have a separate eSIM for internet when traveling to my home country) and that would confuse the configuration.

Other that this, I don't know what may have causes the issue.

Any idea?

Thanks

Ricardo

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