An appointment for the personal enrollment for summer semester 2019 is only required until 29th March 2019.
For degree programmes with admission restrictions be sure to meet the enrolment deadline, stated in the enrolment application document (Immatrikulationsantrag)!
More appointments for personal enrolment will be released progressively.
The booking of the appointment will not work until you "request enrolment" in campo.
The username is the applicant number (Bewerbernummer) as shown on your enrolment application document.