Issue with PDFs as attachments

We used to be able to add a pdf as the second attachment so people could see the weekly bulletin in advance. Suddenly, when you click the pdf it loops back to the same page and you can no longer download the pdf.

Here’s an example: https://www.aisquith.org/audio-sermons/?sermon_id=1904

Any suggestions/solutions?

https://www.ads-software.com/plugins/sermon-browser/