My R-button isn't responding properly.

I've tried blowing on it (it worked, but only temporarily), I've tried pressing on it repeatedly hoping it would loosen it, I've even tried using a toothbrush, but my R-button won't work. I really don't want to go through the trouble of taking it apart because I don't want to mess something up. I've had my New 3DS XL since June 2015 and I've been taking care of it. I haven't dropped it or anything like that.