how to verify identifier on zotero

arminhasanpour

Hi I Recently got this massage on zotero and i dont know how to fix it!
https://s3.amazonaws.com/zotero.org/images/forums/u15833743/rhfol8zjjzdziwe8m2fl.png

dstillman

https://forums.zotero.org/discussion/123954/doi-lookup-not-working