Get out of timeshare contract. We bought in Florida

We are trying to find a way to cancel our timeshare contract with a Summer Bay Resort in Clermont Florida. The mortgage s paid but we feel we have definitely not gotten our money's worth. Every time we try to book someplace there is no availability. We were told that we could travel anywhere using this timeshare. A few years ago there was a sinkhole on this property and quite honestly we are a little concerned with staying there. We had called to see if they would buy it back but they said they do not do that. However, in the contract it says that they have right of first refusal. Would you be able to help us make sense of all this nonsense?