Edit Weights tool not working properly

Hi! I was rigging an asset without much problem, but after I reimported only the geometry on the skelletal mesh, to apply some tweaks I did to the model, I noticed that I can’t save changes on some random vertex’s weight.

In skeletal mesh, I go to skin in editing tools, I click edit weights, I apply full weight for a bone in the problematic vertex, I click Accept so the changes to my weights should be saved, and the vertex gets reverted to the incorrect state. No matter how many times I try, the same few vertices are failing to store any new weights I apply.

Never happened to me before, I just updated my project to UE 5.6 to benefit from the quick render addition.


A video showcasing the issue in 5.6. The same steps in 5.5 work as intended, so something broke in the latest version for the edit weights tool.