you may use "GPS Status & Toolbox PRO" app to find out whether your device is getting connected to GPS satellite or not/having the proper signal reception?
To do so, launch the "GPS Status & Toolbox app" & then switch to your favourite Navigation app. while you get the message "Awaiting GPS or whatever it is?" immediately switch to the said app and observe the GPS co-ordinates which are being received by your device. If there is no activity then it may be a device dependent issue but before reaching out to any conclusion, you need to corroborate various factors which can be the root cause for your problem.
Also, try to latch on other Cellular Operator other than that of Airtel & observe the outcome.