I recently wanted to switch from Optus, so I ordered a sim from TPG. They didn't have any TPG sims left so they sent me an iinet sim. I gave it a try and wifi calling works. I then wanted to port my number from Optus, so I had to order a new sim. This time they sent me a TPG sim, and I ported my number to it. Wifi calling does not work on this sim. Same handset (Motorola G60s). I can swap from one sim to the other, and verify it only works on the iinet sim. Wifi calling options verified all the same.
Is this a limitation of TPG sims? If I get another iinet sim and port to that, will wifi calling work?