iPhone 15 Plus connection issues

I have an iPhone 15 Plus and three days ago is started disconnecting and reconnecting to the internet over and over again. It literally happens continually and just cycles from connected to disconnected.

I have reset my network setting. It does it when on Mobile data (WIFI turned off). It does it on WIFI (Mobile data turned off). I have restarted the phone. I have made sure that it is up to date. Nothing has worked.

I have not got a new router, or a new phone case, or new carrier. Nothing has changed, except that it keeps connecting and disconnecting. The internet (and any internet based apps) are essentially useless. And it's eating up my battery as it works to connect and disconnect repeatedly.

I have Verizon, if that helps.

Thanks!