Help for some reason my game keeps deleting the save files

Ok for context I bought it on Xbox a few years back then got a laptop recently and downloaded it expecting to have to start over and to my suprise at first it had everything including my save with over 28 days of playtime but then I login one day and it's gone and I was like ok I'm getting bored with that save anyways so I create a new one but then I press give up when I got a deadlus hammer as the first item at the start cause I wanted to use the sword instead of the bow and my save was gone and every time I make a new one it deletes it