Reliance Jio Infocomm — sudden decrease in speed

Address:

Hyderabad, Andhra Pradesh, 500052

I live in Shivarampally. I use my JioFi for internet access. And it used to give just fine speeds upto 10-15 MBPS but for the past 2-3 days, the speed is just pathetic. This sudden change has come without any reason and the location is the same. I use JioFi at home. So there's no fault of the device. And also, other phones in the house with Jio sim are receiving great speeds. But this particular no. is not receiving speeds which can be considered even usable.
Kindly look into it. Thanks.