Button issues on v4

So to make a long story short, I have a v4 with some pretty bad button issues. It seems that every button is being pushed at once when I put a battery in it, even when I'm not doing anything. When I push A or B it goes into pause mode and if I hit any button after that the clock just comes up and goes back over and over. I've opened it up and cleaned both the button contacts and the pads that touch the circuit board inside the buttons but it didn't help anything. Anyone have any ideas? I wish it worked. It might have something to do with the fact that parts of it are from another V4, because it went through the wash and there were some blank spots in the LCD screen, so I switched the screen and the paper background from another V4. All the other parts are original, but for a while the buttons that were inside that tamagotchi I had in a v1 that had a missing button, and so for a couple years the B part of the circuit board inside was exposed to the air. Could it be wrecked for good? Does anyone have any idea how I could fix it?

This same thing happened to my Music Star when it got wet. I fixed it by taking it apart and wiping down the circuit board; and then I put in new buttons from another Tamagotchi of mine.

When did it go to the wash ?

It went through the wash several years ago, but it worked just fine other than the screen had about 1/4th of it where no pixels showed up. I finally got around to switching them a few days ago.

Update: I switched out the circuitboards between this v4 I've been having problems with and the one I had for parts, and the other one seems to be fine now. Thanks for trying to help me! Someone can close this topic.

*question answered, topic closed*

Ra,