I'm not able to create neither Sandbox or Production keyset after new development application registration (username: uppership.test). Also I have the same issue when the username was changed for my another one application (username: uppership.dev) and previously configured sandbox disappeared. The error message "An unknown issue has occurred. Contact the website administrator" is displayed just after the login. When I try to create keyset I give the "Issue with creating keyset. Please try again later" message.