I found who was it

I contacted a experienced person in this kind of matter he wrote -

The issues with the story:

-How did the "impersonator" get his email address in the first place?

-The "impersonator" uses the shortened for "u" for "you". From what I've seen of your posts in your club, you don't do this. But BlitzGod does, frequently. So linguistically, the style of the impersonator points to him.

-The "impersonator", if genuine; seems to have done this in a very incompetent way.

Firstly, there's the language thing, as I mentioned.

Secondly, the "impersonator" didn't specify which members to remove. If you really did want to remove members from the club because you didn't like them you would specify; so if the "impersonator" wanted to be believable they would have said something like "kick everyone from the club except this list of people".

Giving vague instructions would also have risked BlitzGod contacting you on chess.com for clarification, which would have unravelled the whole scheme. This feels too poorly-done to be some masterplan from an outside force, and more like something someone would put together in ten minutes as a cover story when they got busted.

-In the same way, if we are to believe his story, we are to suppose none of the above things made BlitzGod suspicious. If he is indeed innocent he has to be extraordinarily gullible (and as such probably shouldn't be on the admin team anyway).

-None of your many other staff mentioned any email like this, at least not publicly. It seems a bit convenient that the "impersonator" just happened to contact the most gullible member of your admin team first. You'd expect, if genuine, other members of the admin team to say "I got an email a bit like this, but it sounded like nonsense so I deleted it".

-The alleged motivation of the "impersonator" doesn't make much sense. According to Blitzgod he did it so he could blackmail him into plugging his club. But really, plugging a club in another club doesn't usually cause all that many people to join, unless the club that's doing the plugging is gigantic. He would probably get more people from promoting his club legitimately using the invite function.

And he has nothing to back his blackmail up. Obviously no-one is going to start kicking people due to emails from random impersonators anymore, so it's clear this was never going to work from any angle.

While it is unclear what the motivation actually is , someone using it to promote their own club sounds implausible.

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One thing that might help clear this up is the chess.com moderation team. It sounds like BlitzGod claims to have a chess.com private message chain with the "real culprit", if that's the case I think chess.com moderators can read private messages to verify their contents and whether the dates line up. They could also check the "real culprit"'s IP address and BlitzGod's IP address and see if they match.