if you want the history, download & install MobWifi - Mobile Hotspot Meter - Android Apps on Google Play
Tap on the hotspot name to edit your mobile hotspot name and password. Return to Dashboard once set up is done.
If desired, turn on data limit per hotspot session
Tap on the toggle at the top of the page to turn on/off your mobile hotspot.
At the end of the session, you’ll receive a receipt for your records. Also, a log will be stored in your History page, where you can access all data usage records.