Copies of my main world keep getting corrupted and I cant delete them

Put the summary of the bug you're having here

What I expected to happen was...:
I would get a single saved copy of my world that was identical to the main world 

What actually happened was...:
the main world does copy over successfully, however, the next time I open the game, my main world is fine, but the copy i created is all greyed out and I can no longer open it. It says it has become corrupted and I can't delete it. Now I have over 35 un-deletable world on my account and need them deleted

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
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