Aside from "learning to spell hypnotized or just trusting your phone knows better than you," there are a bunch of tricks we use.
Staring at it and going over the code path
Talking to a proverbial duck
Going out for a proverbial cheeseburger
Sleeping on it
Half of these tricks force the brain to stop confirming and start seeing, which is our biggest error source. The rest of these tricks let the problem ruminate in our subconscious which is sometimes really good at solving shit.