When you install and run the Mia Travel or Mia Nucleus apps you are asked to allow the app to access different features of the phone, including location.
Newer versions of Android do not show "All the time" an option any more. You need to go to the privacy settings on your phone and update the location settings
for the app.
This video shows you how to enable always on, by going to the settings on your phone.https://youtu.be/btqJo-Lu3Bw