I’ve been pulling my hair out on this, but I think I’ve tracked down the problem. I had moved my WordPress installation to a subfolder on the server and left out a simple line of code, and the ACF was still looking in the old location for the api.php file. For some reason, some things were working and others weren’t. But I think I’ve fixed it.
I Believe that solves this issue as an error on my end. Sorry to use up your time!
