lost saved game

Hi. I was busy playing Dragonstone 2nd time round and was on level 4. Tonight when starting up it has started from beginning again. Lost all the info and puzzles from before... anyone know what I can do to get it back....
thanx
Carol

aaaa any help here. I started the game again..got to level 6 (after couple days) and then got error report..."error..unable to save game".. then it starts up at level 1 again.???
anyone got any ideas....
thanx
Carol