It going to be hard for me to help you find the issue because I can’t reproduce it. Have you tried deactivating other plugins on the site or switching the them to the WP default to see if something there is causing the issue?
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Browse through ideas, snippets of code, questions and answers between fellow ACF users
The most recent ACF Chat Friday featured a live demo of how to register CPTs directly in the plugin, one of our most requested features. Check out the summary below for a replay of the demo, and don’t forget to register for the next session! https://t.co/k2KQ3WWBAz