I have spent the last 3 weeks working with Apple on the same issue. After troubleshooting for literally hours, restoring my iPhone 15 4 times in different ways, having Senior Support extract data for their engineering department and talking to 4 different Senior Advisors (a whole other story), they finally agreed to send me a new iPhone today. The advisor I spoke to today did admit that they are receiving many calls related to the issue and that there is a potential software issue in 18.3.1. He alluded to an update coming soon to fix the issue but in the meantime, I am not getting notifications about some very important texts from doctors, pharmacies, family, etc. which is extremely frustrating as I rely on my phone solely after I got rid of my landline. I will follow up on this post as soon as I get the new phone and upload my data but I have a feeling that it will still be an issue if the software is still 18.3.1 on the replacement iPhone. Another issue that has presented itself is the inability to add my primary debit card to my wallet......a card that has always been in my wallet in the past. So glad to see that there are others experiencing the same issue and that I'm not the only one. It only gives confirmation that it's not user error!