Blue Star India — dealer is not supportive

Address:

Budaun, Uttar Pradesh, 243601

I bought AC of bluestar 3star 2 ton from your dealer - ERA Radios in bareilly. After installation i got to know that there is no gas in it. I complained to the dealer. They send their technician after 48 hrs. with so many calls. He checked and told that there is a leakage in compressor. I told to dealer to change it but he denied and ready for repair. I agreed. After repairing they charged me 2500/- without any bill. I called him why should i pay as i am taking a defective piece and initially there should be gas in it which i did not get.
What the dealer said listen- I will not listen any of your complaint. Your warranty is finished in 2 days. Is this right to talk to customer?
Please take a good step or i will go to consumer forum for complaint against him