Maestro is a multi-national debit card service owned by MasterCard. Maestro is MasterCard's main debit brand and is the equivalent of signature debit card Within the EU and certain other countries. The Maestro does not require electronic authorization, similar to the Visa Debit card. The credit card number must pass the Luhn Algorithm Check. Every Maestro card number has a specifically prefix 50, 56-69.Re-Generate
If you want to validate a credit card number, here is a Credit Card Validator.