Mesh topo utterly messed up in roblox engine

Few of my meshes are messed up in the roblox engine for some reason, I have no idea what could be causing this
Meshes have been fine until very recently, it’s like that both in studio and in-game
This is not caused by flipped faces, I have imported them with all faces facing the right way, it seems like the meshes just decimated and maybe some faces got deleted or flipped, something like that

This is how my models looked before:
image

And this is how they look now:



Some of the models have not changed at all, only few did but it’s still a big issue for me since im reusing alot of the models that got ruined
I am almost 100% sure this is an issue on roblox’s end, I hope there is a way to fix it