Airtel — slow internet & web speed

Address: Barshul Unnayani, 713124

Slow internet speed including apps, web browser, cloud, streaming, youtube, dowloads even from playstore.. Maximum speed i get is below 40kbps instantly for last 2-4days (25, 26, 27, 28th feb-2019).
I hv 3 smartphones with 3 airtel 4g sim (4g net pack active). Ihv try so many methods to recover the speed like rebooting, reseting, sim switcing, data roaming on/off, apn, etc.. But still not get in to 4g speed.

My airtel no. [protected]; [protected]; [protected]