Repoman's right, but there are actually two versions of "fully off" for ESP. If you want the "really really disabled" version, you need to do a steering wheel dance.
Check out pages 379 through 385 of your manual. From page 384:
"A steering wheel/ESP button maneuver must be performed to permanently disable ESP and defeat the functionality of the ESP switch. Repeating the procedure will return the system to normal ESP operation and restore ESP switch functionality allowing ESP “Partial” or “Off” modes.
The following procedure will disable (or re-enable) ESP functionality in the vehicle:ESP operation.
1. Shift the transfer case into the 4H range position.
2. Turn the steering wheel until it is centered and the
wheels are pointed straight ahead.
3. Cycle the ignition key OFF to ON.
4. Wait approximately five seconds for the system bulb
5. Turn and hold the steering wheel one-half turn to the
6. Press and hold the ESP OFF button for seven seconds.
7. Turn the steering wheel back to center, and turn and
hold an additional one-half turn to the left (counterclockwise).
8. Press and hold the ESP OFF button for seven seconds.
9. Turn the steering wheel back to center.
10. Press and hold the ESP OFF button for seven seconds.
11. Cycle the ignition key to OFF.
After performing the ESP disable procedure correctly,
“ESP OFF” will be displayed in the odometer for approximately
12 seconds each time the ignition is moved to ON.
Repeating the ESP disable procedure will re-enable normal
If you're so inclined, you can download an electronic copy here: (https://www.jeep.com/hostb/crossbrand/owners/en/