The first thing that comes to find is that some other setting (who knows what) is keeping it from hibernating. #1, check your manual -- especially the *-marked footnotes. #2, do a reset to factory settings through the MENU. #3, make sure the battery is a SONY and fully charged.

ONE minute? Seriously? Maybe 10, possibly 5 if still on the original 3 year old battery but 1 minute seems ridiculously brief, but then I never considered any power down option after getting a 2nd battery. (Camera might inertly be remaining on to override what it considers an unreasonable user operational decision, like recording slow motion video without a lens attached.) 

A7rIV Power save start time set to  1 min but camera remains on. Any suggestions?