Why are the receipts going over two pages?
The most common reason for this is the totals table has either the headings or the details in the total cells wrapping around onto a second row.
To fix this, you need to adjust the width of the columns or remove a column in the receipt totals. See Using Letter Builder to adjust the totals section.
After you have made an adjustment, locate a Payment Txn using the Letter and then press "Receipt" button to preview.
The below screenshots show examples of text wrapping that can cause the receipts to go onto 2 pages.