Unable to save "pdf" file

[RAMd®d]

Can you view the pdf?

Sometimes I can use Cmd-Shift-S to save a pdf I'm viewing.

Often I have to this when Save doesn't work and there's no Save as... option.

Other times there is the row of five icons in the email -

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Download <—

Other times, two fingers on the trackpad bring up window from which I select Download.

I have no idea if any of these apply in your case.

I may be misremembering, but on one occasion I think I had to turn off my VPN to download a pdf.