There is nothing insignificant or strange in this. Though I'm not actually sure if the reason for your ban is what you are calling a mistake, but if that is true, then here is what could've happened:

klkentkl got banned before you (probably for plagiarism, though I couldn't manage to find any proof since it is an headache to surf over 165 pages of bounty reports in order to find a plagiarized post). And then you used the social accounts that he (klkentkl) has been using, to submit some reports, which technically makes you the alt of that guy, or him yours (doesn't matter, actually). Now, if you have already read the rules and know about them, then you should know that there is a rule about ban evasion (Rule No. 25 in Unofficial list of (official) Bitcointalk.org rules, guidelines, FAQ) which is, that a person whose one account is banned from the forum is not allowed to create and use another account. The only thing that person can do with the newly created (or the other) account is to open a ban appeal and only post in that thread.

Moral of the story: You used another user's social accounts, and it made you look like it is an alt account of yours. When that guy got banned and you were still posting, you were found to be guilty of ban evasion hence getting you banned as well.

P.S: What I said is only what might have happened, and is solely based on assumptions. There is no solid proof of this as of now except for the posts that Veleor has brought up.