Tevion SD card?

I have a 2GB Tevion SD card for my digital camera, I have used it a few times with no problem but now I have a problem where I have tried it in 3 different cameras & first it was saying card error but now it just freezes & we have to take the batteries out, & on another camera it was saying Reformat!! Does anyone know if I have lost everything Or how to rectify the problem? Many Thanks