If you do not act to confirm your card by entering in the 4-digit code (or your card cannot by confirmed), the charge will be refunded 75 days from the date of the charge (60 days in Brazil). Based on certain jurisdictions (such as Brazil) the credit may not actually post to your card for up to 30 additional days.
If you remove your card or close your account during the time frames above, the return of the credit may not process. In these instances, you may need to contact PayPal Customer Service to have the charge refunded.