That’s up to you. You have three options.
1. Sell the car, pay off the residual and lease another. If you sell it for more than the residual, then you get to keep the profit, tax free!
2. Extend your existing lease and hang onto the same car a while longer.
3. Pay off the residual and keep the car. This would only be advisable if you were not employed anymore, for example, if you were about to retire. Otherwise, a novated lease would most likely remain the best way to own a car.