A few days ago, my 2018 XC90 with ~83,000 miles had a dashboard "Gear Lever Locked" warning and lost power on the freeway in a way that reminded me of some sort of limp mode. We made it to the shoulder and turned the car off then restarted the car. Same warning. Turned the car off again, waited longer and the message disappeared. The car drove normally before and after the warning with no visible issues. The warning did not reappear. The Volvo dealer looked at it today and did not find any mechanical issues or relevant error codes. They also did an ECM software update. Any suggestions on next steps? I'm not sure I can do anything else unless or until it happens again with a persistent warning message. The dealer charges a steep diagnostic fee, so I really don't want to continue to bring it in and have those fees pile up into real money without finding the problem. Of course, it could have been a software "glitch" that won't happen again.