I chat with my Chinese friend using sms, her number should looks like "+86 123 0000 0000", but the message app display it as "+1 (230) 000-0000" and create a separate conversation for this wrong displayed number, but phone app works fine.
iPhone 12 mini
If you use correct International prefix the iOS devices will format the phone numbers in the same way as the country does. This is irrespective of what settings you have on iCloud or any other email contacts account.
Watch the GIF below
Thank you for your explanation!
I double checked my contact information and I can make sure I have added the +86 before the phone number.
BUT, when new message come in, it display a separate conversation like this.
Wrong number display when sending sms
