PLEASE HELP!!!!

downloaded this and it won’t even let me into the program because it shows an error code for login..doesn’t get to a login screen even "{"code": 403, "error_type": "OAuthForbiddenException", "error_message": "You are not a sandbox user of this client”} please fix this or give my money back”

Tiggarroo about InstaViewer for Instagram, v1.06