I am sorry about your missing line.
You will not be able to do a sim swap on a line that was not registered by you. However, ask MyCustomer who registered the line to visit...
I am deeply sorry for your missing line.
Kindly contact your bank to prevent an authorized access to your bank account if the line is linked to your bank accounts.
Sim swap by...
Y'ello, sorry about the loss of your SIM card. To retrieve your lost SIM, kindly visit any MTN outlet with your NIN/NIN slip, a valid ID, the lost SIM pack, or a sworn affidavit...
You can retrieve your NIN by dialing *346# on the phone number you registered with and it will cost you N20. To link your NIN, please dial *785# and select 1