Please follow these steps:
1) Start by deleting the Sensate app, then download and reinstall the app
2) Please restart both your phone and your Sensate device
3) If you still have problems, please let us know in an email, the make and model of your phone and check what signal strength you are getting on the bottom right corner of the app when disconnecting
4) You can also send a Feedback response from within the App (sprocket on top right corner), which will auto-include your phone or device details