I would like to apply for tourist/transit visa for hongkong .

I am an engineer and working since 5 years. I would like to visit hongkong on my liesure time probably October 20 to november 1st 2015. I had sent my documents as instructed on immigration site by courier. Finally I got mail from immigration office and knew I am rejected. I couldn't get any specific reason to avoid me to visit Hk and also they didn't suggest me to submit further required documents. How can I apply to visit Hk for about 10 to 12 days.