In addition to the ringtone, the Xiaomi smartphone can also select its own notification tone, regardless of the folder in which the tone is stored.

However, it should be mentioned that the own sound for notifications should be available in a suitable length: If a music title is defined as a notification sound, how it is played in full.

Android 10 (MIUI 12.0)
Step 1:  Open the  Settings
Step 2:  Tap on  Sound & vibration
Step 3:  Tap on  Notifications
Step 4:  Tap on  All ringtones
Step 5:  Tap on  Choose local ringtone
Step 6:  Tap on  File Manager
Step 7:  Choose an  audio file/ringtone
Step 8:  Tap on  OK
  1. Open the Settings
  2. Tap on Sound & vibration
  3. Tap on Notifications
  4. Tap on All ringtones
  5. Tap on Choose local ringtone
  6. Tap on File Manager
  7. Choose an audio file/ringtone
  8. Tap on OK

Xiaomi Instructions