Rmagoo is probably right. Spring for a small can of CRC electronic cleaner, not the giant economy size, because it is very injurious to the ozone layer. DISCONNECT the battery, and then take the can with the thin plastic tube, shove it into the key opening as far as you can, and flush it. Wait a while for the liquid to evaporate, reconnect the battery, punch in the radio code you forgot to memorize, and that will probably cure your problem.

On a related note, if and when the individual windows begin to fail, and they will, it's because the little contacts inside the separate switches corrode from the arcing, and you have to take them out, touch up the contacts with a piece of fine grit sandpaper or scrape clean with your Swiss Army knife, treat them with your can of CRC, and reinstall. Dick