4iiii viiiiva Heart Rate Strap Won't Pair with IOS Iphone7

 My Viiiiva Heart Rate strap worked perfectly with my iphone5s running ios10.1, just purchased an iphone 7 and upgraded to ios10.2 and now Zwift will not pair with HR strap.  I have paired with the 4iiii app and it shows up in my Bluetooth settings on the phone as being paired.  There are other apps on the phone that are reading the HR fine, just Zwift that is having a problem.  Run Zwift on Ipad and it finds the HR immediately.  Just the Iphone 7 that is having a problem.  Any help is much appreciated.  Thanks!

You need to unpair it from all other apps and devices since Bluetooth can only connect to one device/app at one time. The Zwift app should be the ONLY thing that it should connect to.