We can easily delete the created guest account or second space from the Xiaomi smartphone. This can be done directly from the main profile (Device Admin), but this function is also available in the second space settings.
After deleting the secondary space, all data contained or created there will be deleted and cannot be restored.

Note: To delete the secondary space, we need to confirm the Mi account password.

Android 10 | MIUI 12.0
Step 1:  Open the  Settings
Step 2:  Tap on  Special features
Step 3:  Tap on  Second space
Step 4:  Tap on  Delete
Step 5:  Confirm with  Delete
  1. Open the Settings
  2. Tap on Special features
  3. Tap on Second space
  4. Tap on Delete
  5. Confirm with Delete

Xiaomi Instructions