My URL for downloading is expiring

Hi there, first thanks for your great plugin is helping us a lot. We are a non-profit volunteer platform, and we use the excel link to give access to the volunteers applications to the nonprofits that publish volunteer opportunities with us.

We are experimenting an issue, the link that we generate in our gravity forms just work for a few days, after that it stop downloading the file and redirect you to a page with text and symbols. Then we go to the form to regenerate a new url, and it works again for a few days, and then it happens the same thing again.

Thanks in advance for your help

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