From Longman Dictionary of Contemporary Englishget your wires crossedget your wires crossedCONFUSEDto become confused about what someone is saying because you think they are talking about something else → wire
Examples from the Corpus
get your wires crossed• Somewhere along the line, some one had got their wires crossed, that much was clear.• We got our wires crossed and I waited for an hour in the wrong place. 