My ACF plugin seems to have stopped working. The version is 4.3.7. I had updated it to 4.3.9 and it did not work, so I went back to 4.3.7.
I do not seem to be able to add or delete any field!
I use it on WordPress 3.8.5
Hi @carlaturchini
This error can arise when there is a plugin conflict with a new version of the ACF plugin.
It is always recommended to first investigate by deactivating all other installed plugins and switching to one if the stock WP themes to identify the culprit.