Appointment at Ausländerbehörde (Frankfurt)

Hi everyone,

does anybody know how can I get an appointment at Foreigners' Authority in Frankfurt (Ausländerbehörde) without actually going there ? They don't have any online services and never answer the phone calls. The building is, as expected, crowded all the time and I don't want to spend the whole morning in the queue just to schedule an appointment with an officer.

Thanks for your help,

Deniz