Ive tried to book a time with one of Ginza's girls right after the new roster has been updated on the website. However, everytime I tried to call the manager, he claims that she is already fully booked. While I respect what has happened, and thus not blaming anyone at all, I would like to ask for advice on how to increase my chances of success next time.

For reference, Ive been trying to go for Helen specifically several times, all without success. Any advice would be much appreciated.