This error usually means that the administrator credentials for your device are incorrect or not being recognized. Please try re-entering the administrator credentials for the device you are trying to install the app on.
1. Go to App Studio and login
2. Select the Devices tab
3. Select the Edit icon next to the device
4. Clear and re-enter the Device Username and Device Password
5. Select Submit
6. Try to install the app on the device again
If this does not fix your issue, please let me know.