Airtel — airtel 4g speed is pathetic

I have been using a new airtel 4g pre-paid sim since 1st week of june. Until about a month ago i was getting the speed o[censored]p to 4 to 7mbps when i measure it using speedtest.net application. Since last 2 weeks the speed has been very badly hit and is pathetic now at 0.57mbps to 1.2mbps when i measure at different intervals of the day. This does not support me for work from home nor my kids who need to take online classes.
There is no option through which you could reach out to customer care to explain the problem. I feel stranded on a network that claims to be india's best!
I need this to be fixed in the area i'm working at expeditiously. Pls help.