iPhone SE occasionally won't receive calls, I get missed call notification instead
It's probably worth rebooting the phone, just in case, &amp; checking your carrier settings are up to date [Settings > General > About] but ultimately I'd speak to your carrier.

I had a similar issue last year which was resolved by getting a new SIM. Apparently, I'd had the old one so long I was several firmware generations behind &amp; the new card just fixed it immediately.