Downspout put on (Pawtucket)

I had a 12’ gutter installed with a new downspout…The downspout connects into the one on the side.
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I now think with rain/water coming from both downspouts together it’s causing a leak in my basement from double the rain gusting out?,Never had this happen until the downspouts were connected together.
You can see from the pic how the downspout comes down and over connecting into the other.
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I want to have them separated so each gutter has its own downspout.
Can anyone who does gutters help with this project…Want it done ASAP!