How do you get rid of a flat wart on your face?

A wart is caused by a virus and grows rather quickly (months) and there are many medications by prescription or over-the-counter that can be effective. Since it's on your FACE, I'd see a DR...Dermatologist. If it has been growing for YEARS it is probably a SKIN TAG and can be removed in a doctors office. See a healthcare professional to reduce the chance of scarring.