cadillac cts2 automatic switching problem

Hello all. I’ve been having switching problems with my cadillac cts 2 3.6L automatic transmission for more than a year. The switching broblem is as follows. When I drive normally it switches cleanly from 1st to 6th gear. When I give kickdown the engine turns me to the red area, no longer switches into a higher gear and automatically throttles away my gas. If I then go from the gas, it switches again into the next higher gear and drives normally. yes. Gearbox. Control unit in the gearbox. Gm itself says errors unknown. Air filters change and spark plugs. Haha. So, I have read a lot about this crankshaft sensor. Ask you. Could it be the crankshaft sensor? Nothing is stored in the error code. My workshop ( GM representation ) is at the end. So, now to you. Can it help me in God’s name?