References won’t auto-save

In previous versions of Endnote, one could make changes to a reference and simply close it in order to save the changes. There is a box to tick, “don’t show this again?”

Now in X9 whenever I close a reference, I get a dialog which says “Do you want to save the changes you made to the reference?  Your changes will be lost if you don’t save them”.  Saving adds an unnecessary extra step. And the box  “don’t show this again?” dosen’t exist.

How do I get the auto-save functionality back?