When to call
Call when the shifter is seated, the dash lights up and the wheel moves freely, yet the key stays put. At that point the cylinder or its release has failed, and harder pulling tends to end with a snapped blade. Tell us whether the key reaches Lock and whether the engine still runs, since those answers point to the part.
If the car still starts, book the repair for whenever is convenient. No tow comes into it, because the cylinder is swapped wherever the car is parked. The ignition repair page describes the replacement in detail.