iPhone 6 freezes on the last (6th) digit of the PIN

Debub wrote:

... but if I don't try to unlock, I can receive calls and take photos and see notifications.

This makes sense, as you have previously allowed these actions from your lock screen (Settings > Touch ID & Passcode > Allow Access when Locked).

It sounds like you are mistyping the sixth digit of your PIN. Anyway, see this:

If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled - Apple Support

Hi

Are you sure that the passcode is correct have you change it from 4 digits to 6 digits

Try a reboot press & hold power button & menu button hold both down until you see apple logo .

If you still have a problem go to iforgot.apple.com

Cheers

Brian