Unable to send pictures/gifs

I was recently abroad in Mexico when my issues started. I tried sending sending a few pictures and videos. It started off fine, but the last 2 of 8 days, I kept getting a "Not delivered." message. I thought it was because I wasn't on WiFi. Unfortunately, the problem persisted. I thought it was a weak WiFi so I waited till I was back stateside. Again, the problem persisted. I thought it was because I had not updated by to iOS 17, but to no avail.

Is anyone else experiencing a similar issue? I am using a 14 Pro Max. I have tried restarting the phone, force restart, making sure MMS is enabled, I'm not short on space, etc. What else can I do without restoring the phone?