In this event please try the following: Make sure that your entry does not have capitalization. The app will not default to capitalization when you first registered, so if by chance you capitalized a word on registration, the app will have that word in the registered data. The login entry’s must match.
Another issue may be to try adding or taking away a blank space after the username entry and/or password entry. This also could have happened at data entry on your signup.
Also you can try to reset your password. On the login page bottom, just add the email address that is associated with your account, press enter and reset instructions will be sent to that email address. Please be sure to not use capitalization or add any accidental spaces.
Try these above methods first before contacting support. – firstname.lastname@example.org