Painted Foliage floating and flying

I have only seen one other person with a similar issue but they did not find a solution. In my project that has been brought into ue5 from 4.26, all of my painted foliage is either flying around in the air, or sliding around to or away from the camera as shown here:

This is really frustrating because to repaint this amount of foliage will take me days!

there are “flush” cache commands you can run that might help try that.

No idea about this issue, but shout out to Towers.
Just up the road from me, I used to work there years back.