Hi @Nik121,
Welcome to the PayPal Community!
I am sorry to hear you are having issues adding your card. From my knowledge, all Visa and Mastercard's have a 3 digit CVV code. Only American Express cards should have a 4 digit CVV.
If your card is issued by Mastercard, I would suggest you contact your card issuer. They may have provided you with an incorrect code in error. Unfortunately, our system will not accept a Mastercard with a 4 digit CVV code.
If your card is not being accepted, please try adding an alternative card. If you require any further assistance, please don't hesitate to contact our Customer Support.
I hope this helps!
- Rachel
