It's not uncommon for your LG smartphone to display duplicate contacts. If there is a contact with the same name, phone number or email address, the LG device will detect this and ask for confirmation. However, after importing contacts, you can display them twice. If you only want one location, you can merge the duplicate contacts.

Note: Double contacts are merged together and can be separated at any time later.

Android 9 | LG UX 9.0
Step 1:  Open the  Contacts -App
Step 2:  Open the  Menu
Step 3:  Tap on  Manage contacts
Step 4:  Tap on  Merge
Step 5:  Tap on  Merge  or open the  Menu
Step 6:  Tap on  Merge all
  1. Open the Contacts-App
  2. Open the Menu
  3. Tap on Manage contacts
  4. Tap on Merge
  5. Tap on Merge or open the Menu
  6. Tap on Merge all

LG Instructions