How do I fix the LED in my CapsLk key?

Recently, the LED in my CapsLk key has refused to turn off. Before, it would light up when caps were on, but go back to being dim when caps was off—then I tried “press and hold”, but now the light just stays dim and flickers when I type different keys.

The issue started yesterday; and my laptop had ended up dying, so when I turned it on, I still had the same problem. I was told it might need cleaning, but I’m not sure what exactly I’m doing. Any advice would help.