"Found name clash" error

Hi! I have a Skeletal mesh (SM1) in my project, and I want to import the same rig with other meshes skinned to it (SM2). So when importing, I select SM1 as Skeleton. Problem is that I get a ‘FAILED TO MERGE BONES’ error. So I tried to import SM2 by itself to see what the problem might be, and get the error “Found name clash, node ‘Body’ was renamed to ‘Body1’.” I think that is the cause of the issue.
Why does this issue occur? There is another joint called BodyRoot that could cause the name clash, I guess? The first time I imported the rig (SM1) there obviously wasn’t a name clash. Could there be some history in Maya that messes things up?

I have the same problem importing characters from Blender. There are either two root bones or the name is changed to root01. Usually the former.