If the cruise controller shows a solid red light.

Most likely the controller does not have a data connection with the bike.

Ensure the Diagnostic plug is connected and fully seated.

Check for bent pins. These are very fragile and easy to bend pins.

See here for more detail

The controller has been pre-programmed for your bike; no programming is required. However, if you suspect problems with this factory setup, manual throttle setup is possible.

If you get a check engine light, or the bike goes into limp mode when trying to SET cruise:

1. Ignition ON, engine OFF, throttle in closed position.
2. Press the SET button 5 times slowly.
3. Blue LED will flash slowly.
4. Hold throttle fully open. Press the Cruise CANCEL button. Any other button or timeout of 60 seconds will cancel this procedure.
5. Throttle positions are now learned.

https://youtu.be/NTCSbwuB6WU?si=pSjWDf_nWiJsRvkJ