Why does the L3 button register as L2?

My Switch Lite of 3 years has had a funky relationship with the L3 button, or the button attached to the left joystick. Perhaps through repeated use, the button stopped making a clicking sound and eventually only making inputs on less frequent occasions, making me opt to reversing the controls of L3 and R3. Today however I noticed that L2 (ZL for reference) had stopped making the clicking noise as well. When I went to go inspect it using the test input devices feature on the switch, L2 would make an input of L2, but so would L3. So far there's been no water damage to my Switch Lite and I have tried resetting it already. How would I go about fixing this?