Hyundai Motor India — Spare tyre size smaller

Address:	Darjeeling, West Bengal
Website:	consumercomplaints.in

I purchased Verna SX 1.6 on May 3, 2017. On May 10, one of my trye got flat, so i when i took out the spare tyre, it was of different make and size.
The four tyres are of Bridgestone Radiu 16 and Spare tyre MRF Radius 15. When i complained this to company, they said since July 1, 2016, it is their policy to give different tyre for spare. Now I have following points to discuss:--
1. How can a company give different tyre as spare, it will make the vehicle unstable, thus compromising with the safety of my life.
2. Nowhere during the sales process i was told that the extra tyre would be of different size, i would have rather paid the differential price.
3. One of my friend brought the same car around 5 months back and he is having all 5 tyres same. I checked some new vehicles also, all 5 were of same size. I have got the photo of my friends car and the new car also.

I had brought this car from Kaushal Hyundai, Matigara, Siliguri . Since then I have been talking to the dealer, call centre and R.O at Kolkata with no response, please let me know what should be my plan of action.