Gutter people

[HarleyDog]

Ok, clickbait title I know. You came here to figure out who I was calling gutter people. However, it does apply to my question. Who knows about gutters? I had some installed and I think it was done incorrectly. My gutter sags in the middle instead of giving that slant to let all the water out. Plus, water leaks between the gutter and the wood it's screwed into? WTF? I think when I see the guy who did it, I'm gonna slightly punch him in the face because I already asked him to fix it once, which he did come down, but problem remains. How do I fix? Do I need to totally remove the gutter?

JK on the punching in the face, but I can't honestly say it hasnt crossed my mind a few thousand times.