Hello.
Let's first understand what a dump is?
in simple terms, this is information that is recorded on the magnetic tape of the card, which carries data. It is these data (account, balance, PIN, cardholder's full name, etc.) that make it possible to withdraw money from ATMs and pay for purchases in the store.
I'll give you an example:
B4000001234567890^PETROV/IVAN^03101011123400567000000;;4000001234567890=031 01011123495679991
In this example, B4000001234567890^PETROV/IVAN^03101011123400567000000 is the information of the first track, and 4000001234567890=03101011123495679991 is the information entered in the second track. You should not try to use the algorithm for constructing the first track using data from the second one, since the example above is only a visual aid, and different banks use different templates.
Now let's take a closer look at the first track: it starts with the Latin letter B, which indicates that it is a bank card. 400000 123456789 0 - this is the so-called card number or PAN, as it is called by professionals, 400000-BIN, which can be used to determine the bank that issued the card, and the type of credit card itself, 123456789-the card number in the bank.
The zero at the very end of the PAN is the check digit. ^PETROV/IVAN^ - name of the card holder. 0310 - card expiration date, i.e. the date until which the card is valid. In this case, it is October 2003. 101-service code. It is usually 101.1 - the key number used to encrypt the card's PIN code. It is only needed when working with an ATM and for operations where PIN is required. 1234 is the encrypted value of the PIN code. You need it in the same cases as the key number above. 567-CVV, the verification value for the card number. It is obtained by encrypting the service code, PAN, and expiration with a pair of bank keys. CVV2 is obtained in the same way, only the service code is replaced with zeros, which is why the values of CVV and CVV2 differ from each other. The second track is similar in many ways to the first, but it is the main one, and with it, you can build information from the first track.
The credit itself is a white plastic that carries the function of a matrix on which information about the dump is recorded. The recording is made using the MSR unit, which can be purchased now approximately on free sale if you just Google it.
Conclusion: the PIN code is encrypted, so you won't be able to see it through the software and the card reader.
I think you were simply deceived, when you pay 100 euros, you will receive an incorrect PIN code.
If the seller knew the balance and PIN codes, he would easily cash out the card dump himself. This is a typical deception.