The issue began [xxx]. I drove to Napa, stayed for about 20 minutes. When I started the vehicle again and started driving on the highway it was revving but not going above about 10 mph. Had to pull off the road. I waited a few minutes turned it off and back on and it drove normally and I got back home. It’s been doing the same thing intermittently since then but more often and throughout the day or drive. When I come to a stop at a stop sign or light and start driving again it will get stuck in 1st gear and not switch out until I turn the vehicle off and on again. This has happened in traffic several times. The dealership has not been able to diagnose it or fix it since they have not been able to reproduce it. They have kept it overnight three times I believe and once had a tech take it home for this and other issues including issues with the proximity sensors that they also haven’t been able to correct. No warning lights appear. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)