NUH Private

I’d like to change my appointments to private from subsidiary at NUH. I emailed them but have yet to get a reply so I called as ask for the availability of my preferred doctor. However, he said that I should inform the doctor attending to me on my next visit myself. When I asked about it to the receptionist on my previous visit, she said to call the general hotline. So which is itttt???#advicepls