"Couldn't Save Content Please check your internet connection and refresh the page." Safari iOS

I download a lot of PDFs. I use iOS Safari. Half the time, I have no issue saving to Dropbox, but the other half of the time, I get the following error: "Couldn't Save Content Please check your internet connection and refresh the page." My workaround has been to use Save to Files where I have Dropbox linked, but this is, frankly, annoying because Files has its own issues (ie, it will often abandon a Dropbox folder randomly and bring me back to the default Files>Download folder, and it lists dropbox folders in alphabetical order among the files and god forbid I use the search box for fear of the first issue happening), and it's more time-consuming. I also tested Chrome just now, and it saves the same files to Dropbox without issue, but I shouldn't have to use Chrome to use Save to Dropbox reliably. I like Chrome on my PC, but I like using the native web browser on my phone.

I've been having this issue for MANY YEARS—with at least two different model iPhones (7 plus and now 15 pro). It does not matter what network I’m on. It's been a consistent ongoing issue. I would consider upgrading my Dropbox plan except for this problem.

Also note: I pulled up the same file (in Safari) that wouldn't upload earlier, and, just now, "Save to Dropbox" seemed like it would work ONCE but gave me the error on several subsequent attempts.

Something I've noticed but not sure what it means: a lot of the PDFs I download are patterns, and a large portion of those are from Ravelry. Although this issue is definitely NOT limited to Ravelry, I have noticed that patterns from there tend to be stored either with an address starting with "pdf-inline.ravelrycache.com" or "s3.amazonaws.com", and trying to Save to Dropbox the PDFs stored at the latter location ALWAYS produces the error; whereas, files coming from the ravelrycache location Save-to-Dropbox without issue every single time.