Problem with replacing imported instances.

I can't seem to find a solution anywhere. I'm trying to make 2+ versions of multiple identical houses, to be specific. I imported the geometry, instanced it many times, but when I try to change the original geometry by reimporting, only the first geometry changes.

I tried importing with collapsing/no collapsing by material and/or keeping the hierarchy, even with single mesh objects, still the same problem.

A workaround might be to manually replace every mesh with the new one, but is very time consuming.

Hopefully I missed something and someone will enlighten me.

Thank you!