That error shows up if you have not configured your citation style to render a certain item type or the item doesn't have any of the metadata filled in to render it.
Say you have a style that you configured for journal articles, book chapters, books and reports. Now you cite a webpage, but the citation style doesn't know how to render it, since you didn't put it in the code.
Which style are you using? If it's something you made yourself, share it via pastebin.com If you're using an off-the-shelf style, what item type are you using?
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Say you have a style that you configured for journal articles, book chapters, books and reports. Now you cite a webpage, but the citation style doesn't know how to render it, since you didn't put it in the code.
Which style are you using? If it's something you made yourself, share it via pastebin.com
If you're using an off-the-shelf style, what item type are you using?