13" MacBook Pro Beeps 3 times

Hi, I’m new to the site. When I try to turn my Macbook 13” on I get 3 beeps followed by 3 more beeps again. This problem had happened 2 months ago but it resolved itself when I traveled with the laptop on a flight, I’m guessing from moving around in the bag.

The beeps suddenly came back now. I opened the Mac to see what was wrong and saw nothing visually wrong with the RAM but did see a corroded screw near the battery connection (pic included). There was no water damage to the laptop. From what I saw, the RAM cannot be removed from this model or cleaned under because it is soldered. Is there anything I can do to fix this without breaking the bank?