Can't access resume saved game

[Sharkman Briton]

So, I wanted to change my sandbox game to science, and I went to persistence.sfs and changed the mode to SCIENCE and the thing next to the save title SCIENCE too, and copied my sandbox games persistence thing to the new save, along with all the craft, then saved and booted up the game, I can't click on resume saved game, nothing happens, I tried making the save file again and it says I have to overwrite it, meaning my saves still exist, I went back to my persistence and changed the thing next to the saves title to SCIENCE_SANDBOX and it still doesnt work, and when I did make a new file when I went out of it i couldn't access resume saved file either, so the game is impossible to play. Please help me.