PDF viewer on mobile can only be downloaded and not viewed

I have a PDF viewer on my site that’s connected to specific PDFs on airtable. I can view them fine on desktop, but when I open on a mobile device it is greyed out and has a blue button that downloads the PDF when clicked. Id like to be able to view the PDFs within the viewer on all devices. Is this possible? I’ve attached an example of what I’m seeing.
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