Thank you for your help
We fully turned off caching in GC and disabled the system cache plugin, but our cache continues to regenerate and the error seems to reoccur periodically. We've been unable to isolate any specific cached item as the culprit so far and don't know why the site continues to generate a cache when it's turned off, but are still troubleshooting.
We have only the invisible reCaptcha plugin enabled on our site, and all the required fields for login are enabled.
Do you know why these Virtuemart items continue to be cached?