If your Key timer is stuck at 0, make sure your device clock is set to "Automatic" and shows the current date and time.
To set your device time to Automatic:
1) Go to "Settings" on your device
2) Select "General" and then "Date & Time"
3) Make sure that "Set Automatically" is ON and that your Time Zone is correct.
If you are on mobile data, you may also need to turn it off and connect to WiFi for a few minutes. Defective cell towers nearby can sometimes broadcast inaccurate network time information.