I’m not familiar with this sportsbetting website, Do you mean nitrogensports or really that particular website? Anyway deposit bonus is common offer by the casino for new players and sometimes they are adding free spin on top of the deposit bonus to make new players will be encouraged to play on there casino. The only problem was there wagering requirements which is so high and almost impossible to clear by just casually gambling unless you have patience to bet only small for a long period of time. I don’t know if there’s really someone manage to complete here but it’s very rare.