"Upgrading" from Snow Leopard (10.6.8) to El Capitan (10.11)

So here's the deal, I am attempting to "upgrade" my OS to El Capitan from Snow Leopard but I am having issues with the App Store not working properly.

Following the link from the Apple website, it prompts my App Store to open and everything seems to be working fine. I click the "Get" button on the App Store and I am prompted to login with my AppleID. However, once I login I get a prompt that says "Software Update Required - To make changes to your payment information, you need to upgrade your Mac to the latest version of macOS."

I think that what may have happened is that the first time I went through this process I was prompted to update my billing information because it was out of date or invalid or something of the sort (can't remember exactly). So I logged into my Apple account on chrome and updated my billing info hoping that this might might work itself out but I keep getting the same prompt. I have attempted to restart my computer and sign out of the App Store but nothing has changed.

I am then prompted with this:

There is nothing in the "Updates" tab of my App Store (except upgrading to High Sierra, which I need to get El Capitan before I can consider doing that). Other than that, my software is up to date according to the Software Update from the Apple icon.

It seems like an issue with the App Store but I could be wrong.

Is there any way to reinstall or "reset" the App Store so that I can get out of this loop?