Did you try rebooting twice? Seriously though, could just be a miles thing or you may be following steps incorrectly. Worst case, back to dealer and have them diagnose.
It's a little weird to use. I don't remember the exact steps I did but I got the error message once.then tried it differently and it worked. If I remember correctly you have to be holding the brake when you hit OK
very unlikely you have a faulty line lock system. Like i said, first time I tried it, I got the error and it told me to see the manual. I ignored it and tried again except did things just a little different, as I explained earlier. Play around with it, it is more than likely it's just user error. It isn't the most user friendly feature but it works and isn't too hard to figure out. The manual also isn't 100% clear either.
When I got the "see the manual" message I let off the break before I hit okay to initiate the line lock final step and it cancelled out the whole thing