Hello Soomumbau70
We are aware of this error and are endeavouring to find a solution. This error occurs with any invoice for GA and half-fare-cards at this moment.
We apologize for any inconvenience caused and thank you in advance for your understanding.
If you need the invoice to pay your GA travelcard as quickly as possible via e-banking, you can alternatively pay your GA Travelcard invoices at any ticket counter or by calling the following phone number: 0848 44 66 88 (0.08/min)
You’ll find further informations regarding travelcard invoices here.
I wish you a nice evening.
Greetings
RahelW