Crash on saving

I played the game for around 2 months before the new version was announced, and ever since the Beta was made public, I have had problems while saving my old farm. It just crashes without the "saving the game" message appearing.
I made a new one just to check if it was the farm's file or if it was the game, and the new one worked just fine.
The problem seems to be only with the old one, since when I opted out of the beta I could play and save it no problem.
I thought it would be fixed when the actual update came out, but the game keeps crashing just on that one file.
Wondered if anyone had experienced something like this on their games, or if anyone could help me figure out how to fix it.
Used SMAPI in order to play multiplayer before, but when I stopped using it the game still worked just fine, so I dont know if it may be a cause.

Sincerely, thanks in advance for any kind of help with this