How to delete duplicate contacts from Samsung mobile phone

If your mobile phone contacts are repeatedly displayed, I suggest you: 1. Try to change the contact display mode to mobile phone or SIM card. 2. Check whether the third-party synchronization software is installed, and you can cancel the contact function of the attempted synchronization software. 3. Back up data (contacts, text messages, photos, etc. ) and try to restore the factory settings. 4. If the problem still exists, it is recommended that you take your mobile phone, purchase invoice and maintenance card to the local Samsung after-sales service center for testing.