Airtel — airtel 4g hotspot not working properly

Address:

500018

I am using 4g hotspot. It is not getting connected with green signal. It shows up wireless network connection and says that the connection is excellent. But the fact is it gives yellow signal and it is getting disconnected.
From what i understand green indicates 4g, yellow is 3g. It is also erratic, off and on every few seconds. Is the problem with the instrument or is it the tower nearby