Report ID: 405895073
Zotero is not accepting downloads from Chrome plug in or DOI Add by identifier. Everything looks fine in Chrome, but the entry doesn't show up in Zotero. Also, the DOI takes the identifier and looks like it is processing, but then just sits there and never finishes.
Upgrade Storage
After that, try resetting your translators from the Advanced → Files and Folders section of the Zotero settings.