I am using a Xiaomi Redmi 6 Pro mobile. Both 4G and 3G data works fine with my Belong sim.
When I share the data connection over WiFi hotspot, the connected device does not get internet.
I inserted the same SIM in another Samsung mobile,and the hotspot is working fine. That means the SIM has no problem.
I tried several troubleshooting steps including factory reset, but was not successful.