Have be hearing about people claiming to be scam while using the pos machine not until I experienced it today.

I run a pos business were people come for there daily transactions, today I was in my shop when a guy came in that he want to widraw money so normally I collected is atm card slotted it in my pos machine and I put in the amount he wanted (30k), so I selected his account type which is saving then I now gave him to input is pin number, lol and behold this guy have to erase everything, change the 30k to 1k and  put his pin then press enter to complete or approve the transaction.
After he collected his card and gave me back the pos machine for me to  pay him I now brought out money counting to pay him something just move me to check the transaction first that was when I realized it was just 1k he widrew, I confronted him and he could not even oughter a word.

What am saying fruders have taken there fraudulent activities to another level so we all need to be extremely careful and watch full with our daily transactions.