In order to continue your studies in the next semester, you need to re-register. The re-registration is being requested by payment of the semester fee and, if necessary, the tuition fee.
The re-registration period for summer semester is: January 15 to February 15.
In your C@MPUS-Account (application "my payments") the total amount payable is indicated. Besides you will find an official notification of fees with a list of the single amounts and the total amount in the application "my student dossier".