I have found Riley to be very prompt at answering texts - every time I send one.
I feel fortunate to have seen Riley a number of times. She is (and can afford to be) somewhat selective in who she sees, and is understandably cautious when connecting with first time clients.
My only advice would be to communicate with respect and always be polite. If you have been a gentleman in your communications and have still not received a reply, I would assume that there is a legitimate reason and as Birdboy said - perhaps time to check out one of the other great ladies in the city.