I am confused by your post, are you having difficulties uploading or downloading? If you are having trouble uploading files to Adobe Stock please post your question on the Stock Contributor forum.
If you are having difficulty downloading files from Adobe Stock, is it only one particular file or is it an issue with all files? If it is a single file please post the asset ID so I can investigate. If it is all files then please review the following:
Clear your browser history and restart your browser.
If you have any browser extensions or plug-ins, disable them. It may be one or more extension causing the issue. You may have to use trial and error to find the culprit. Anti-virus is often a cause.
Is the issue occurring when you download to a particular library or all libraries? If your library has too many assets or has a corrupted file downloads to the library may be blocked. Reply to this post if this is the issue and I can offer additional assistance.