RE: 37 University Club
If you bought it new, I would contact the dealer (HobbyTron?) that you got it from (I googled "University Club 37" and they popped up as a dealer).
Since it's a single channel radio, it's almost impossible to isolate what the problem is. If it were a 2 channel boat- which is the norm- you could swap the servos between channels and help isolate the fault to a servo- or something else. As it stands, it could be any part of the radio- the transmitter- the receiver- servo- or the batteries. I assume you've got fresh batteries in both the transmitter and receiver?
It's unfortunate that models such as this are even sold... they are so inexpensively made they can't last. The money spent on something like this would have been much better spent on a better model, one that has both rudder and sail control. An R/C sailboat without control of both these functions can't be taken seriously. Even some of the more expensive "ready to sail" models from importers require a few upgrades to be reliable/controllable on the water. You get what you pay for, unfortunately- the time to ask questions is before you buy, not after. I would consider it a lesson learned.
Wes