There are two ways to apply a one time discount to a member's next invoice in the Triib admin site: Discount Next Payment, and Adjust Invoice.

Discount Next Payment:

Open a member's profile by searching their name in the Search Members box at the top of your admin site. Navigate over to the billing tab and on the right side of the screen, enter the appropriate info under the Discount Next Payment header.

Adjust Invoice:

To simply edit the dollar amount on a member's next invoice, click the payments tab on their profile, then select View Details for the invoice you'd like to edit.

Next, select Edit item:

Enter the adjusted price:

Save.