Gear stuck while driving

While driving in slowly (twenty km/h) in first three km's gear stuck to some position and car revs up when accelerating but not gear changed and still moving slowly. No engine mil pop up. At this situation, nothing happens if I change gear selector lever and the only solution is the engine restart with the gear lever in neutral position. Then everything is okay and no more trouble with in traffic or slow driving again. This happens in once a day. Several attempts were done with obd scanner, but no DTC found out.
Thank you