@Bot_234 Hi. sorry to hear about your problem. It is possible that the saving operation was interrupted by the operating system itself, and once this operation is interrupted the file gets corrupted because it fails to save the main file that strings the drawings together.
In most cases you can recover a partial amount of work by following the methods on this guide: Pencil2D Project File Corruption Prevention / Partial Recovery Guide
But if you want you can also send us your project file so we can recover whatever is inside of it. You can upload it here: https://www.pencil2d.org/contribute/share.html
The only problem will be that we can recover the drawings, and where they were in the timeline, but not how they were positioned on the canvas, so you probably will have to re-position the drawings again on the canvas. The procedure we will perform is the same as described on the guide I linked first.