Hyundai Motor India — supply of wrong size spare tyre

My hyundai santro sportz, april 2019 model has been provided with a wrong wheel size of r13 whereas my car is using a tyre size of r14. Then i request the car dealer to change tyre, they answered me that this the norms of the company. Why is this, why cant the company provide the correct size of tyre. If i dont get a satisfactory response from the company, i prefer to return the car.