Volkswagen India — replacement or a full refund of my new vento

Address:

Mumbai City, Maharashtra

Hello,
My name is sanjay naik.
I purchased a volkswagen vento tsi highline plus petrol on the 30th of december 2017 from volkswagen downtown prabhadevi, mumbai.
My engine number is cbzk38873
Chassis number is mexh17603ht145468
My ownership experience has been pretty disappointing to say the least.in the first week of purchase i could hear a rattling sound coming from the underside of the car. I was not sure from which side it was actually coming from. I thought that it would be a passing rattle and would disappear by itself but that was not the case unfortunately. Other problems that i would also like to note are that of my front armrest creaking when resting my hand on it. It was a genuine issue as i got it rectified from the service centre.
Also the rear left hand side door wouldn't open from inside. It turns out that some cable in the door handle was loose and they got it fixed.
My main complaint is the unsatisfactory quality of materials used in the car. I have heard people saying that german cars are well built and have top notch interiors but in my opinion it's a big let down.
Coming to the workshop topic now. My car had been dropped off to the service centre on 11th of january 2018 for a general inspection. The main issue of the underside noise wasn't addressed, but a new issue cropped up in the form of a front driver side window noise that was unexpected of. My front armrest sound was also fixed. I got back my car the same evening. I drove it the same evening and i could hear a unrefined noise coming from the rear. Well i thought it was addressed but it wasn't to be.
My second workshop visit was on 24th of january. I waited there the whole day and issue wasn't rectified. The service advisor and his team took 6 trial runs of my car and they were struggling to identify the noise. They were supposed to give me some update on my car today i. E. The 25th january 2018 but i didn't get any specific response in respect to the noise, but i got a casual answer saying that the work is still going on. The car still remains to be at the service station as i am writing this. So i received my car on 26th feb at 2:55 pm. The sound had gone but there was a black stain on the driver's seat. I also felt that the transition between the reverse to the parking gear wasn't smooth as before. It feels a bit hard. The driver who dropped off the car always gave me the invoice. The invoice has a long list of parts that were replaced and refitted in my car like the shock absorber, steering gear etc. This is not acceptable on a new car. It's barely been 25 days since i got my car and it feels that the car is a year old. I had never imagined that they would change some parts on my new car. I am totally unhappy. I had also told my advisor to polish off a few small scratches on my car which he didn't look into. The scratches still remain. I cannot keep sending my car to the workshop again and again. The car also wasn't cleaned perfectly form inside.
I am not pleased by this attitude and i would like a replacement of the car and if that's not possible, then i would like a full refund