Try this risk free easy method
Maybe your speed can increase
?
You need to Install Internet Speed Meter lite app from Google Play
Make sure your mobile network is connected to Band 40
Install JioTV application in your device > Launch ‘RIL AGM’ Channel > Set Quality to High
Keep on checking the speed meter and note down maximum speed
This will gives you best speed while streaming any video
If you still got the slow speed just try to check this on non-busy hours. So at that time you will find maximum speed.