I have activated 4G on my Airtel SIM, but whenever I try to recharge the 4G pack on Airtel, the website says I need a 4G SIM even though my SIM is already 4G. Who knows about this issue?
I have a Airtel 3G sim, now recently I bought a 4G(LTE) compactible device what should I do to change my sim to 4G?