Library saves deleted

A few weeks ago I tried to save something to the gallery and an error came up that said "library storage full" so I deleted one of my gallery saves so there would be space. When I tried to save it now I had space, it came up with another error saying "a gallery error came up", this normally happens so I just didn't save it thinking nothing of it.

A few days passed without playing the sims/going on the gallery and yesterday I went on and tried to look at my gallery. Everything is gone apart from the system gallery such as townies and houses.

Is there a fix for this where I get my gallery back? Or is everything just gone sadly. I had lots of unfinished sims and houses from the gallery and would be a shame if it was all gone.