1) go to settings
2) on the search bar add: apps
3) Select option: apps
4) Select: "more" option. The 3 dots at the bottom of the screen
5) select: show system processes
6) select: dialer
7) select: Storage
8) select: clear data
This should resolve the issue.
Hi Deon. Check your contacts, make sure it is showing the correct list. Also, go to Settings > Apps > look for the Phone app > Clear data. If problem persist, please directly contact your carrier, the problem is probably on their end.