First, unless you can demonstrate that the merchant misrepresented in some way what the customer was purchasing, there is no valid chargeback right. MasterCard protections do not cover buyer's remorse.
Second, if you do choose to spend the time and money on a chargeback provisional credit is covered in Section 1.4 Chargeback Stages, of the MasterCard Chargeback Guide.
It is very important to note that when an issuer has billed a transaction to its cardholder’s account for payment and then chooses to exercise a chargeback right, the issuer must credit the cardholder’s account for the amount of the chargeback. Under no circumstances should an issuer ultimately be reimbursed twice for the same transaction.
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