Not repairing my karbonn k1616,Not refunding me money,and not give me anew mobile

Location/place: Azamgarh,up

Name of company/service: Karbonn

I boaught kabonn k1616 of 4200 rupees in may .My mobile not working properly.I send it care three times for repairing but they not repire my mobile and refund my money and not give me new phone
pls take action on them