first phone call to some of my contacts ends right after they answer

This has been happening ever since my friend got the new 17 Pro. The first call to a few of his contacts always ends at their end after them answering the call.

Right after this, if another call is made from this device to the same person, that call connects fine.

Apple customer support is not willing to create a ticket and get logs from the device until we contact the carrier and get a case number from them.

This is clearly not a carrier issue since he never experienced this with his old 14 pro, with the same carrier.

What can we do to resolve this? It has been 3 weeks since he purchased the device, so returning is not an option