Thanks for your help raising this issue.
I believe I have found and fixed the problem.
If possible, please login to your online account and click on the ‘See all versions’ link next to your ACF PRO license. On the following page you will see a new version 184.108.40.206-RC1 available for download. https://www.advancedcustomfields.com/my-account/
After replacing the plugin files, can you please let me know if this fixes the issue?
Please also remember to hard refresh your browser to clear cached JS.
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