Guttering problem, too much water - overflowing?

Somebody messed yo up, you can't have enough downspouts, sounds like they shorted you about 5 of them, and the spot where the water hits the gutter should have an overflow shield on it and it should never back up into the roof. So, you can't stop it temp, you have to fix it or take it down. You need a bigger gutter, rain stop, and big down spouts.Gutters, you only notice them when it rains and they backup and don't work and fill with leaves. I will never use them again.