I’m afraid I can’t reproduce this issue. Could you please try to reproduce the issue on one of the WordPress’ stock themes (like Twenty Fifteen) with other plugins deactivated? If the issue disappears, then you can activate the theme and plugins one by one to see which one causes the issue.
If the issue persists, please contact firstname.lastname@example.org and provide them with some screenshots, your ACF and WordPress version, and step by step to reproduce the issue.
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