Able bought a number of books from The Book Box Store Limited in a single mail order, and enclosed a cheque for $240 with the order, drawn on the Big City Bank. In the interval between mailing the order and the arrival of the products, Able noticed a number of the books (totaling $120) were available at a lower price at a local book store. On the day the books arrived, he visited the bank and was pleased to see that his cheque had not yet been cashed. He placed a stop payment order on the cheque, and in filling out the request slip, placed the words "goods unsatisfactory" in the box allotted for the reason for the request. Able sent back the part of the order that he had now bought more cheaply elsewhere, and assumed that The Book Box Store Limited. would send him a new invoice for $120. The Big City Bank failed to immediately enter the request into its computer system, and as a result, on the arrival of the cheque a day later, it paid Able's cheque out of his account in the normal manner. Able discovered this error in the course of using an automated cash machine a few days later, and asked the bank to correct the error. The bank put $240 back into Ables account and told him that they would collect back the $240 that they had paid The Book Box Store Limited 's bank, The Business Bank. The Big City Bank returned the cheque in the clearing system, now marked "Payment Stopped," and demanded $240 from The Business Bank. The Business Bank refused the stopped cheque and would not make payment back, stating that by accepted banking convention, too much time had elapsed between acceptance by the Big City Bank and the return of the item. While this had been going on, The Book Box Store Limited had received the goods returned by Able and had mailed him a refund cheque for $120, for as far as they knew, they had been paid in full. Able was pleased. Clearly a computer error had sent him a $120 cheque rather than a $120 invoice, and he ignored the whole matter. Assume another week passes. Discuss the events that follow, and the positions of the parties, with respect to the law of negotiable instruments as it is written. In advising the banks, what would you suggest that they add to their standard form account operation agreements?