This isn’t the first time an iOS update has messed my phone up.
What troubleshooting steps have you tried?
Reset Network settings is your best first step. It will reset the settings for all 3 radios. Cellular, Bluetooth and wifi.
If this does not help, I suggest restore to "factory" using iTunes and set up as a new device. Use the device for a short time to see if the behaviour stops. If so, do not restore your backup. If the issues stay, you have a hardware issue.