Not to worry! First and foremost, please know that your Upside balance isn't gone. We don't delete funds from the app, so your earnings aren't lost! Trouble-shooting your account depends on the type of account you have. Since you can sign up for Upside with either Facebook, Google, or email, the trouble-shooting is a little different for each type.
Have you changed your Facebook email recently? Remember if you change those credentials, your Upside login will change, too! For more info on Facebook-based Upside accounts, please check out our page here.
First, try clearing your cache! You can do so by tapping Settings > Apps > Select app> Clear data
If that doesn't work, try updating your Google Play Services, and that should in turn update the app and clear up the issue!
Make sure both your phone's operating system is updated and you're using the latest version of the app! You can either update the app, or delete and reinstall Upside to get to the latest version.