It's so confuse.

I tried to change my "Real Name" in "Edit user profile" to name, that already exist, and ... Now we have games X vs. X, but it is not same person. Is it a "bug"? Or something different?

Hmm, you mean: there're two different persons on LG with the same name. Maybe you can use an extra: a middle name, a nickname or...you can sue him/her if it's a copyrighted/registered name :)

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