Lenovo - Lenovo Ideapad Gaming Laptop Not Working Well

I had purchased Lenovo Ideapad *i i* laptop from Flipkart last year in August. It was working fine for * to * months. After that I started getting lags in gaming. So I after some time I complained to customer service. They checked my laptop through remote login. Installed and reinstalled graphics drivers again and again for like * month. Then they told me that we will change your motherboard. So their engineer came and changed the motherboard of my laptop. Even after that games were not working well. So I contacted the premium support again and they said that the senior team will call me withing ** hours. The senior team called me and checked my laptop again, and then he said that that you have storage issues which is very absurd. I tried to make him understand that none of the games are working. But he was not even ready to accept it. After that I tried to call again but my numbers were blocked on all of their customer care numbers. I called them with a different number and asked them to get a call from a senior team and I also asked them why my numbers are blocked so he said that it is an network issue, I asked him I was not getting any network issues before the gaming issue. So after that I got a callback from the senior team. He said that go to service center, if people at service says that there is problem in the laptop then we will resolve your issue. So I went to service center. They asked me to format my system, So I tried after formatting my system but the issue was still there. So I again went to service center and they said we would reinstall windows. It took them * to * days to reinstall the windows. But the problem was still there and I called them . He told me that we cannot provide support, only games are not working well and the rest laptop is fine. So I asked them my device's name is Lenovo Ideapad Gaming *i and I can't do gaming on it. I have even registered a grievance against them. But till now I have got no replies. They are not replying my emails nor my phone calls.
On their site, it is mentioned that GTA V will run *** fps plus, But it is hardly ** to ** fps and there any many more games. And they also mention that the battery works for *hourse on normal use. But I hardly get *hours of usage.
Thanks,
Hoping to get my issue resolved.