Hi there! @Nickho Thanks for posting your concerns. I’m sorry to hear you’ve had these issues. The “+” in front of your calls is an issue that started in the network and was later resolved.
If you are getting this, please follow these steps to resolve it:
Go to settings>iCloud, scroll to the bottom and sign out of iCloud.
Go back to settings>messages, and toggle off iMesssage.
Delete any message thread including group messages with the phone number you’ve received the error on.
Turn your phone off for 2-3 minutes.
Test by sending a new message then log back into iCloud and toggle iMessage back on.
Thanks!
Charise