Iphone users including iPhone 5s/6s/7 plus iPhone 8 plus users running on latest iOS 11 are facing issue that imessage on iphone is showing the contact name when someone texted them. Now it is showing only the phone number. Even the normal text messages are all displayed by contact phone number instead of contact names in iPhone.
After updating to IOS11, while contact's phone numbers has a name in the list but in iMessage and message are showing phone numbers instead of Contact names. Also iPhone is showing the contact name for all the text send to the user.
It will not display the saved name in messages or when the contact actually calls her phone. This issue it appears to be a bug that pops up from time to time
There are many fix listed below to fix the issue and show contact names in iMessage:
Fix 1: Language & Region setting
1) Head to Settings -> General -> Language & Region
2) Tap Region and select a region close to you, I am in the US so I chose the US Virgin Islands
3) Confirm you want to change the region
4) check your Messages app, your contacts now probably look normal
5) Go back to Language & Region
6) Change Region back to what it is supposed to be (For me it was 'United States')
Try now, this should fix the issue.
Fix 2: toggle Short Name
Go to Settings > Contacts > Short Name and then turned the Short Name in this menu off, check your messages and it should fix the issue, now you can turn short name ON again.
Fix 3: MMS setting
Tap the home button twice to bring up the app multitasking screen. Swipe to find the Messages app and then swipe up on the preview window to close the app.
Go to Settings>Messages>MMS Messaging. Turn it off and then turn it on again.
Restart your phone and then see if you can see contact names in iMessage.
Fix 4: Edit your contact
Try making a trivial edit to one of your contacts. Then restart the device.
Try editing one contact and added the +1 prefix (country code) to your mobile number and saving it. It should fixthat contact’s name fixed; it is possible that it also somehow fixed all her contacts!
Check again in messages if the issue is fixed.
Fix 5: Default account
Form many users the issue is resolved by changing default contacts from Exchange to iCloud and then switching it back.