Volkswagen cars use an immobilizer security system to keep the car from starting when the wrong key is used. Every Volkswagen car has a particular key that works and this key must be programmed by the dealership. Other correct model keys can still be used to start the Volkswagen; however, when the wrong key is used or someone tries to start the ignition illegally, the immobilizer system kicks in and shuts down the engine. The only way to unlock the engine is to use the correct smart key.
Remove the incorrect Volkswagen key from the car engine. It is possible that the ignition will be locked and you will not be able to remove the key yet; if so, skip to Step 2.