When uploading the required documents in the Backoffice, the error message 500 appears.
First change your password if it does not consist of 10 characters with upper and lower case letters, numbers and special characters: - Backoffice>>My Profile>>Change Password. - Enter your current password and the new password two times (at least 10 characters, upper and lower case letters, numbers and special characters). - Click on the green button "Edit" - Then log out of the Backoffice (important step because the new password is now synchronized) - Now log back into the Backoffice. Afterwards, please log out, delete the browsing history and the cookies and then open the My Support Center via another web browser tab, if possible, in the Incognito window.