Xiaomi
Rename a Contact Group auf Xiaomi
Contact groups in the Contacts app keep whatever name you typed when you first created them. Adding or removing members later does not change that label, so an outdated or misspelled group name stays until you edit it manually.
MIUI only allows renaming for groups you created yourself. Default groups such as Family, Colleagues or Friends are built into the system and their names stay fixed, even though you can still add or remove people from them.
Steps to rename a custom group
Open Tap on Contacts ➔ Open the Menu ➔ Choose a Group ➔ Open the Menu ➔ Tap on Rename label ➔ Enter a Name and tap OK.
The new name applies instantly and every contact already assigned to the group stays exactly where it was. No members are removed and no messages or call history linked to that group get affected.
If the rename option is missing from the menu, you are likely inside one of the default groups. In that case, create a new custom group with the name you want and move the relevant contacts into it instead.