post.php?post=1394&action=edit:1An invalid form control with name=’acf[field_5b4de03311881][acfcloneindex][field_5b4de14e11882]’ is not focusable.

SOLUTION:

 

For ACF Free/non-License users:-

If you have added Repeater Field in Advanced Custom Fields PRO then remove required option from repeater field and it’s child field and update it.
After that you can add required option in parent repeater field only. Do not use required option in any child repeater field.

For ACF License users:-

Simply Just update ACF( Advanced Custom Fields PRO ) from 5.6.10 or less to 5.7.13. In new update you won’t face the same problem.