Fantasy Football.... your answers?

Hey I know how to play fantasy football, and I know you cant pick the same team over & over again, no one gave me an answer to my question....I want to know why Im not givin the chance to pick a nother team for todays game?... I picked the colts last week, they won, that gives me another chance to play today, am I right or wrong?... I DO NOT want to pick the colts again, Im aware you cant pick the same teams. I just want to know why Im not able to choose another team.... So anyone out there smart enought to give me a straight answer.