I fired up Kirby's Dream Land 3 yesterday. Screen didn't display anything which was unusual since it was working fine a bunch of a times before. Take the cartridge and re-insert it, fires right up. Go to the file select screen and all my save files are gone. I checked the battery just now. It is original to the cartridge but measures 3.05 VDC. So another case where a battery measures good voltage but the save file randomly gets deleted.