It sounds that you probably “in game” inserted a exchanged memory card and then tried to save. The way to do it is not in game if that in fact is the case. Start your ps2 with lid open and with the game memory card you want to save in slot 1and a new memory card in slot 2. There is a function there to copy the game of memory card 1 to the new memory card 2. Hope this might help ya...