updating/publishing fails using gutenberg

I can publish using the old editor but not using the new gutenberg editor. I am NOT using cloudflare. The only plugin I have installed is the JSON Content Importer. I get a pink “updating failed” banner as soon as I type in a title. I did not have this problem using version 3.9.8, even though I had gutenberg installed. I am not a coder, so if you can help me, please make the explanation easy to understand.
Thanks!

• This topic was modified 7 years, 7 months ago by ericscottdouglas.

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