iMessage keeps unselecting my number.

About a month ago we switched carriers and upgraded our iPhones. Since then, iMessages on one of the phones keeps randomly unselecting in iMessages for send/receive. When I go to settings to iMessage, my iCloud I.D. will still be selected but not my phone number. I have to go back in and activate iMessage and after a few minutes it will finally reactivate and begin working again. I have tried using it both with and without iCloud as an iMessage option. I have performed every single one of these steps below ad nauseum. My account is fine. My bill is paid. It’s an eSIM only.

I have literally spent hours on the phone with my carrier too. So please don’t reply if you are only going to tell me to do one of these steps below.

1. Check and verify your number in Messages settings 

• Go to Settings > Messages.
• Make sure iMessage is toggled on.
• Tap Send & Receive.
• Under "You can be reached by"and "Start new conversations from", ensure your phone number is selected.
• If your number is already there, try tapping it and signing out of the Apple ID on this screen. 

2. Turn off and restart iMessage 

• Go to Settings > Messages and turn iMessage off.
• Also, go to Settings > FaceTimeand turn it off.
• Restart your iPhone.
• Turn iMessage and FaceTime back on. Your number should re-register automatically. 

3. Sign out and back in to your Apple ID 

• Go to Settings > Messages > Send & Receive and tap your Apple ID to sign out.
• Go back to Settings > Messagesand turn iMessage off for a few seconds.
• Turn it back on and sign back into your Apple ID. 

4. Reset network settings 

• Warning: This will erase all saved Wi-Fi passwords and cellular settings, so you will need to re-enter them.
• Go to Settings > General > Transfer or Reset iPhone.
• Tap Reset, then choose Reset Network Settings.
• Your phone will restart. You'll need to enter Wi-Fi passwords and reconfigure any VPNs or other network settings afterwards. 

5. Update iOS 

• Go to Settings > General > Software Update to check for and install any available updates. 

6. Contact your carrier

• If none of the above steps work, contact your cellular carrier to ensure there are no issues with your account or SMS plan that could be affecting iMessage.