Groups created on the LG smartphone can be edited at any time, allowing you to rename the contact group, add or remove members or change the ringtone.

Note: The standard groups can only be edited to a limited extent.

Android 9 | LG UX 9.0
Step 1:  Open the  Contacts -App
Step 2:  Tap on  Groups
Step 3:  Tap on desired  Group
Step 4:  Open the  Menu
Step 5:  Tap on  Edit group
  1. Open the Contacts-App
  2. Tap on Groups
  3. Tap on desired Group
  4. Open the Menu
  5. Tap on Edit group

LG Instructions