Instead of waiting for Apple to release a fix, iMore suggests downgrading back to iOS 8.
Go to
About
and then
Check for Updates
or visit
iTunes.com
.
Launch
iTunes
on your Mac or PC.
Connect your iPhone 6 or iPhone 6 Plus to iTunes via Lightning to USB cable.
Let iTunes do its thing
That’s it.
It’ll take a little while for your phone to restore, but it should be working after that.
iOS 8.0.1 kill the Touch ID and cell service on your iPhone 6 or iPhone 6 plus?
Here’s how to fix it!| iMore