Please carefully follow the steps below.
1. Copy the number you want to call
2. Paste the number on your phone dial-pad
3. Add “**” in front of the number
4. Call the number, this will ring once and the receiver will get a missed call signalling that you called.
You have successfully call the number without having airtime on your phone. You can repeat the steps to call the person again, it doesn’t have any limit.
Please Note: The above steps work with Airtel sim only