Help! Anybody has booked an

interview I did it on 19th of July and at that time there were appointments available, however, when I paid the booking fee, the booking system showed me that my credit card had a problem.( I PAID THE FEE WITH A visa CREDIT CARD, IN US $) Now with my reference No. the system still shows my info and I find no interview appointments in July and August in US Consulate General in Vancouver. Is it fully booked or is there a problem of the system? Anybody can tell me. Thank you!