I am facing frequent disconnection issue when I connect my TL-MR3620 router with Airtel 4G modem. It works for sometime and then disconnects showing no internet. I need to turn off the router for 10-15 sec and again start it, then it start working but after sometime it disconnects again. This is very frustrating. 

When I connect the Airtel modem direct to my laptop it works fine without any disconnection. 

Below are some additional details

Router model- TL-MR3620

Hardware Version:TL-MR3620 v1 00000001

Firmware Version:1.1.0 0.9.1 v0001.0 Build 170921 Rel.45771n 

USB Modem- Airtel 4G

Make- Huwai

Model= E3372h-607

Please help to solve this issue.