I recently connected my note 9 to the phone plan after using it just for games for a little more than a year. When I opened the app to create contacts, it just had a spinning bar saying updating contacts. It just stays like that, and as of current, I have no way to create contacts. I even tried downloading contacts apps from other sources, but I still can't add contacts.
I would recommend trying clearing the cache data for the Phone app like Samsung_Q7nlI2E recommended. However, if all troubleshooting fails the reset would be recommended.
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