Glitch - My sims keep falling through the floor

[Kaye]

This only occurs in this one game file.

If my sims are upstairs and I direct them to do something, they'll occasionally walk forward and end up on the first floor and have to go back up the stairs. This happens with the toddlers too. If I direct an older sim to interact with them, the toddler may suddenly appear on the first floor and then the older sim must go downstairs.

My sims will also sometimes appear to be walking on the top floor (the shadow of their feet can be seen) when they should be on the bottom and if they're supposed to be on the top, it'll look like they're walking on air if I switch view to the bottom.

ResetSim will fix this temporarily, but it starts again. I tried copying the file and that seemed to fix it, but again, only temporarily. When I played the game the next night, the glitch started again.

I have no idea how to fix this permanently except deletion, which I don't want to do. Any ideas?

[Saltypaws]

I have had this happen too, but for not some time now.  I finally had to put the family in the bin and move them into another house.  I had sims sleeping in mid air.  I did however move some things around in the house and it quit happening, but only for a short time, so finally just gave them another house.

[Kaye]

I had sleeping in mid-air too.

The game is a legacy, so I hate to have to move it, but I guess I don't have a choice. But first, I'll try moving the house. Maybe another lot will work and if not, I'll just switch the house.

Thanks.