Bajaj Auto — v15 battery issue

Address: Hyderabad, Andhra Pradesh, 502032

I bought v15 in the month of march 2018, i have taken a ride for 1 month and i got issue with battery and the electric start is not working. I contacted the service provider with the issue. They have kept the charging for the battery for the first time to see if the issue resolves, after riding for 15 days still i got same issue. I went again to the service provider to let them know about the issue and asked them to replace the battery but they charged the battery again and gave it to me. Again after 15 days it gave same issue. Third time again i went to the service provider, this time they took 15 days to replace the battery. I have take the ride for 2 months and now again the better seems dead and the electric start is not working. I am getting frustrated with the service. Within a span of 6 months of since i bought the bike i had to go the service provider for 3 times regarding the issue. I am getting frustrated with the bike. This will be fourth time that i had to visit the service workshop reagrding batter. Let me know what should i do now. Do i need to sue the company for providing a faulty piece in the name of ins vikrant.