Thanks all. I've been having problems with MailChimp integration too. Any updates?
I've been following the troubleshooting guide.
The results and steps taken identical to @DanC
I'm using google sheets as a backup, as suggested.
Further reading brought me to this:
That first part can't be correct. It contradicts the whole reconnection fix.
The 2nd part: Does this mean I cannot connect a newsletter subscription, and a contact form which includes a subscription to the same list in MailChimp now or something?
I've been using the same forms and MailChimp audience for five years without issues. I've only started receiving this error this winter.