Fnb- home affairs

Why can't I get a booking online for passports in Johannesburg?? I've been trying for the whole week and it always says: 'no time slots available'. The new dates JUST came out, how can it already be full? I phoned for help and was put through to at least 4 different people, including home affairs. Please, we DO NOT want to go to home affairs..avail more dates, or avail more branches... we can't pay and then have only 2 months to visit a branch, when we can't get a booking at all..