Selective Receiving of Text Messages

Hello. I am a brand new user of the iphone. Just moved over from Sprint a few days ago. My question is this...when I had my Sprint phone I would receive several text messages a day ranging from sport scores to weather updates. After getting this iphone it seems that now I only receive text messages from certain parties and no longer from all. Example is ESPN.. I signed up for mobile text alerts a very long time ago but now iphone seems to not want to deliver them. Has this happened to anyone else? I make a living of text messages and need to have ALL of them delivered not just a few.