If we have already activated the SOS Emergency Help on the Xiaomi smartphone, we can add more contacts afterwards in case one or the other has been forgotten.

Android 10 (MIUI 12.0)
Step 1:  Open the  Settings
Step 2:  Tap on  Passwords & security
Step 3:  Tap on  Emergency SOS
Step 4:  Tap on  Emergency contacts
Step 5:  Tap on  Add
Step 6:  Choose one or more  contacts
Step 7:  Tap on  OK
Step 8:  Choose  Cancel  or  Send now
  1. Open the Settings
  2. Tap on Passwords & security
  3. Tap on Emergency SOS
  4. Tap on Emergency contacts
  5. Tap on Add
  6. Choose one or more contacts
  7. Tap on OK
  8. Choose Cancel or Send now

Xiaomi Instructions