Please confirm what is the unleashed firmware version ? Which mobile device (Android, IOS) you are trying to connect with unleashed app?
1- Uninstall the Mobile App in the cellphone and try again.
2- Try to Log in using credentials for Google or Facebook, etc.
3- Test with another cellphone available.
Please check if "Enable Mobile App remote Management" option is enable on the unleashed controller.
Please refer the below KB article-