We need to investigate more what happen during this reimport with the material ID.
The asset can also be broken when the DDC get dirty and the asset is rebuild.
use the same repro step has
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-76986 in the post.
|Component||Tools - Import|
|Created||Jul 9, 2019|
|Updated||Sep 3, 2020|