Unintentional worlds automatically being created

This is something that I have encountered recently. 

On the menu (after the play button on the bottom), there are 2 unnecessary worlds.

Those are the worlds that I can't play, edit or delete. Their creation year is at a future state (12/31/2069). They have random letters/symbols as the name.

I didn't create them, and would like to get rid of them as they crash my game from time to time.

What would the problem be?