Thank you! I’ll look into this
It doesn’t look like you got a response on this. Did you ever figure this out?
It may be too late for you, but I noticed that it was working on a different installation of WordPress. On my local machine, it is failing, and I have Early Access enabled (https://www.advancedcustomfields.com/resources/upgrade-guide-version-5/). It is working fine on a different installation where Early Access is not enabled.
Damn. Thanks. If I come up with anything, I’ll let you know.
Did you ever get this fixed? I’m having the same issue.