How good and pleasant it will be before God and man to see the sanitation of the internet space in Nigeria and reduce fraud.

Fraudsters usually request for airtime or cash.

There can be a law and an agency setup for this purpose.

If a GSM number is reported for fraud to the agency from at least 6-7 internet users, then the agency can mandate the GSM operator to check the call log of the fraudulent gsm number and report back to the agency on its findings, then the agency can go after the owner of the gsm number using his biometrics.
If the airtime used as payment to the fraudster was not sent via share n sell, then the serial number of the cards from the victim can be used to trace the gsm lines into which the airtime were loaded.

As for bank transfers, deposits and other means of payments to the fraudster, when the Agency receives complaints from at least 6-7 internet users alleging fraud linking any bank accounts, the agency will receive evidence of payment made to the account and then forward same to the bank and the bank shall report its findings to the agency. The agency will then go after the alleged fraudster using his biometrics.