In the event a check, draft or other instrument tendered for payment is dishonored by the bank or another institution upon which it is drawn, by reason of "insufficient funds", "account closed" or other similar reasons, a Return Check Charge of fifteen dollars ($15. 00) for each such dishonored instrument will be assessed to the customer. Such charges will be added to previous amounts owed and will be due and payable on the terms and conditions of the original amount owed for which the dishonored instrument was so tendered as payment. ASU may serve a customer on a cash basis for the next twelve months only if more than one check, draft or other instruments of the customer is returned in the previous twelve-month period. Serving a
customer on a 1 'Cash Basis" shall be deemed to mean that payment will be made by customer using U.S. currency, U.S. Postal money order, or certified check.