^^This. If you saw a "3" in the EVIC display, then you accidentally hit one of the shift levers on the back of the wheel. When you engage one of them the tranny shifts into manual mode and won't shift on its own again unless you go into "D".Were you manually shifting gears? How did you know you were stuck in 3rd? Could it be that you've engaged sport mode and the car was waiting on you to shift?
Just the same way you got it into sport mode. One click back to go in and come out of sport mode.^^^ well but this is not all that good either. You already have the car in D and you've engaged sport mode. How do you back to D without stopping the car and shifting the knob?
i guess you can also cycle using the knob between drive and sport modes.
On most cars with paddle shifters you can control the transmission for a while but it defaults to full auto next time the transmission needs to shift. you can only keep the car in the high rpm band you are truly in manual mode. And on most cars you need to shift the lever not simply manually change a gear.
I figured out the same over the weekend. First few days with car. Shifters are very handy for downgrades! Either "+" for 2 secs as Tempest said, or the ->Sport->Drive bump will do it.You can hold the "+" paddle for 2 seconds to exit manual shift mode and return to auto, no need to move the shifter.