Should an open accordion section be hidden when the user clicks on another section?

I'm designing for an enterprise-level software. The software is a repository for different departments to store their files. The content types are Dashboard and Reports but inherently both of them are PDF files. (I know this is confusing, but sometimes you have to work with what you inherit.)

mockup

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EDIT

Thank you for the responses. I can see an agreement in the suggestions to reduce the cognitive overload by keeping only one accordion open at a time. However, what happens when there long list of accordion blades? It works alright for the first blade but I'm unsure how the 8th blade will function? Hide the top blades?

mockup

download bmml source

What should be the interaction? User clicks on 4, should the one on top hide or show below?

I'm more interested in the reasoning behind the interaction.