I recently bought a "sonoff basic" in order to control the lights for my fishtank.
I am able to switch on and off the lights of my fishtank using "EWeLink" app, as long as I am connected to a broadband network. This means my mobile (ios) is on my home wifi (broadband - Airtel)
When I try to operate the "sonoff basic" with my mobile on 4G network (Airtel - India), I always get a message "operation failed, please try later"!
When I went to my neighbour's house and connected my phone to his broadband, I was able to control "Sonoff basic" and operate the lights of my fish tank.
Any thoughts on why I am unable to operate "sonoff basic" when my mobile is on 4G network in India?