iPhone 7 - double tapping home button doesn't work
I have a brand new (reconditioned but brand new) iPhone 7 with iOS 11.2.6.
Double tapping the Home Button to bring up all the open apps so I can close them only works very intermittently. Most of the time, all that happens is that my home screen slides down about an inch or so. I've noticed that if I go into the Settings app and then out of it, about half the time after that double tapping the Home Button will result in being able to see the apps so then I can close them.
The inconsistency is really bothering me. I saw that someone else had complained of the same problem but the discussion was closed without any solution or suggestion.
The home button works fine for everything else. I've rebooted the phone and that hadn't fixed anything.
Is there a setting that i'm not thinking of that I should check? Is this a bug with this iOS update? I just got the phone. I didn't have that problem with my iPhone 5S that was on 11.2.5.
iPhone 7, iOS 11.2.6