Git Subtree Results Subtree in Merge Conflict

I currently have 3 repositories named A, B and C. Both A and B have a folder c, which is a subtree of repository C. Now when I add a new file to c, do git add, commit and git subtree, click to C. When I pull B in, it ends up in folder B c, so it works as expected. But when I then edit the new file in B c and execute the git commit and git push subtree, and I do the git subtree in A, I get a merge conflict.

How to prevent this conflict?