Hathway / Gujarat Telelink [GTPL] — internet speed is not as per purchase plan

I have purchased a yearly plan of 40mbps, when it was installed i was getting around 32 to 33 mbps download speed, then my internet stopped working and i complained about it and it was fixed but the internet speed was reduced to 2-3 mbps. I logged complain with gtpl around 7-8 times but the ticket that i raised is closed without any solution. I am paying 5500 for 40 mbps plan and i am not getting the desired download speed.
I kindly request to look into this and resolve the issue.