watch does not show 6 digit code

Before trying again to pair your watch, it may help to close all open apps on your iPhone and then to restart both devices:

• On your iPhone, double-click on the Home button, then swipe up on each app preview to close it;
• Turn both devices off together, then restart your iPhone first;
  • To turn your watch off: press and hold the side button until you see the Power Off slider; drag it to turn off.
  • To turn it back on: press and hold the side button until you see the Apple logo.

You may then also be able to follow the standard pairing process, without needing to pair manually:

Set up your Apple Watch - Apple Support

Otherwise, when pairing manually, check that you are tapping on the 5-digit name on the screen of your iPhone (when it shows the same device name as that which is shown on your watch, after you have tapped on "i" on your watch):

Your watch should then display a six-digit code, which you next need to enter on your iPhone:

More information:

Set up your Apple Watch - Apple Support

You're most welcome! 🙂