Hi,
I don’t know why this problem starts appearing now :
Whenever I add a Repeater field to a field group, any subfields in the repeater is moved to top level of the field group after saving :



Same here! Possibly an issue in a new version since the subfields I created in another site are still working correctly.
What version of ACF are you using?
WP 5.1.1 + ACF 5.7.12 + ACF Pro 5.6.10
but it’s a multisite
I don’t understand why you have 2 versions of ACF installed. Are you trying to run both of them on one site?
Update Pro to the latest version.
I’m having the same issue. Has anyone been able to figure it out.
WP 5.1.1 + ACF PRO 5.6.10
There was an issue with this that has been resolved in a later update.