Each time i have i have questions like this, i come here.. The the gods (programmers)

My Elder sis fall for one scammer who called her one day and conviced her into giving them her card details plus atm pin..
They later called her to even send back the OTP the bank sent to her.

She had 81,300 naira before the withdrawal, and they took exactly 81,000.

I have been thinking how they managed to know her actual balance, because if they were guazing amounts it will need them to be trying the transactions multiple time untill they narrow it to an amount that works.. I made a little investigation and it was used for an online transaction, jumia precisely

But it just happened once.. Or was it card clonning, niger scammers i fear o!

me too i wanna learn, but my best guess connivance wth a staff in the bank -- nobody wen nr dey hungry this days

This is an interesting topic.
Please we need to be educated.

lol you think a banker would connive with other rogues to steal 81k, when there is sufficient information to siphon larger funds?
From my professional experience, there are levels to fraud....A fraud of 81k would have been caused by divulgence of the customer's banking details, either via the popular fraudulent phone calls or physical contact with customer's card/mobile banking details by a fraudster. As for how they got know the victim's account balance, I guess op hasn't ever heard of mobile banking applications....Simply put, after they have victim's info, they just enroll/reset the victim's account on the app from their own device(thats why they always ask you to call out the otp numbers sent to your phone), thereby all the account info would lay bare before their eyes.

There is another level of fraud where the victim's line would be cloned, the clone-sim recieves all the bank alerts and can be used to move funds via USSD code.... that's a story for another day though.

trytillmake:
me too i wanna learn, but my best guess connivance wth a staff in the bank -- nobody wen nr dey hungry this days

Sadly no post from this section ever makes it to frontpage.
Even the almighty python programming threads never moved lalasticlala the snake king
Nowadays, no one ever has the mind to mention mynd44
And the ghostworkers calling themselves mods of this section, I bet we ain't ready to discuss them yet.
Point is................your voice won't be anyway more audible than the whispers of an ant

Hashimu:
This is an interesting topic.
Please we need to be educated.

Frauds have levels and as rightly said here OTPs are strong form of authentication that can grant full privileges to fraudsters. Once they break/overcome that barrier, they have access to the account