The groups or labels created in the Contacts app on the OnePlus smartphone can be renamed at any time if a typo has crept in or the name does not seem quite right.

Android 10 | OxygenOS 10.0
Step 1:  Open the  Contacts app
Step 2:  Open the  menu
Step 3:  Choose a  label/group
Step 4:  Open the  menu
Step 5:  Tap on  Rename label
Step 6:  Enter a  name  and tap  OK
  1. Open the Contacts app
  2. Open the menu
  3. Choose a label/group
  4. Open the menu
  5. Tap on Rename label
  6. Enter a name and tap OK

OnePlus Instructions