title: ACF Repeater deletes previous entries on update
body: <p>We are having a weird problem. We have a repeater. It used to work perfectly. But now, whenever we add a new item, one of these things happen:
  - recording new item with some of the fields
  - not record the added item
  - deleting previous entries</p>
  
  <p>We tried these:
  - updating wp
  - updating ACF
  - deleting the ACF plugin and installing a fresh one</p>
  
  <p>But the bug still remains.</p>
  
  <p>Please help!</p>