How to create a custom remittance template in Fusion to summarize transactions at cardholder level?

Summary:

We’ve deployed the standard Disbursement Corporate Card Remittance file format for AmEx as delivered by Oracle (GL 1025 file format). This template by default prints the rows at document payable line level, i.e. , sends a record in the file per transaction paid to AmEx. So if an employee had multiple transactions that the company has paid to AmEx on behalf of employee, the remittance file will contain each underlying transaction for the same credit card number of the employee when remittance is generated.

The ask from customer is to send the remittance summarized by credit card number (with sum of all transaction paid on behalf of a credit card number on a particular date). How can we achieve this?