Depending on the notification, there are different solutions:
The account does not exist:
make sure that the website address is correct, as there are different instances of the system,
make sure that the account has been registered and activated,
check the correctness of the entered data (e-mail).
Incorrect login or password:
check the correctness of the entered data (e-mail and password),
change the password by choosing the “remind password” button.
Messages other than those listed above:
contact the recruitment office.