Lost Houses in a world

Yesterday March 24th I went into one of my world saves, I built in several buildings in sveral of the worlds in that save. Today when I went back into my same save, and went back to several of my builds, they looked like the original builds where still there instead of mine so I went into build mode and my build and the original build were gone!! There was a sim I made for the lot and could see her still so went into live mode, she was there but the lot was empty. So I went into a completely new lot to start a build over and the original lots were all empty in all the worlds!! Have no clue wheat is going on. This has never happened before!!! I have been playing since Sims 1 and own all the games up thru sims 4 and this is the first!!

I tryed to recover but it did not work came out the same way. I have 10 other saved worlds and they are all ok.

Thank you for any help you can give Jessy428r