Appliance Repair Questions? Ask a Technician for Answers ASAP
Your model number prefix of 721 means it's made by LG / Goldstar.F9 code on an LG means either a bad door switch or a loose door switch mount.Even though a door switch clicks, it may still be bad inside.This can be caused by slamming the door or by habitually opening the door while it's cooking without hitting the Stop pad first.
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