We have users that sometimes can no longer login to the Stryd app using their Google or Facebook account. One likely reason is that users have multiple Google / Facebook accounts, and are trying to login using the wrong account. One solution is to uninstall the Stryd app, and reinstall it to make sure which Google / Facebook account is being used.
If this does not work, please contact firstname.lastname@example.org. We are able to change the settings on your account so that you can use your email address to login to your Stryd app (be advised that you will be able to set your password, but that you can no longer use your Facebook / Google account)