During the final fight, Happy Hogan calls Nick Fury to warn him about Mysterio's real plan. Happy says a something about going through Tony's old stuff. And Nick Fury replies with "Never call this number again".
Later when they meet up, Happy says "Did you get my coded message?" and that it translates to 'Looks can be deceiving'.
What was the coded message and how does it decode? Was it like a pre-setup distress code or was it a simple 'first letter of a word acronym' kinda code?