[Marttt]

Wrong section, and the snippet provided doesn't give any clue about your exception (the error is the line above "Call stack trace" that you didn't copy+paste)

anyway, your "for" loop is wrong, if you use "return" inside, it will exit the "CheckStatus" function,
use "continue" instead to go to the next index, otherwise it will stop looping in the first "not in game" client