The gearshift button popped out.
Hello. In order to repair this problem, you simply need to get the gearshift knob and button replaced. If you still want to use the car until you are able to get your shifter fixed, you can take a small screwdriver and push where your gearshift button once was and this should enable you to put the car in gear to drive it. However, it’s best that you have this issue addressed and repaired as soon as possible. If you need assistance, a certified mechanic such as one from YourMechanic can service your vehicle for you.