"thanks for the courtesy clueless" = "thanks for being kind enough to ask, you clueless person" (she's being sarcastic). "Clueless" here means "stupid", "dumb", but it's used in a kind of joky way, and isn't very severe or nasty. Possibly the reason she's calling him this is because it's obvious that it's not going well, but in any case I guess the reason is apparent from context.
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