C. Gaston Whiddon owned Gaston’s LP Gas Co., Inc. Curtis Dufour purchased the company. Since Whiddon had personally operated the company for many years, Dufour was worried about competition from him and insisted on a noncompetition clause in the sales contract. The clause stated that Whiddon would not “compete with Gaston’s LP Gas Co. anywhere south of Interstate Highway 20 for nine years.” Three years later, the Herring Gas Co. offered to buy all of Dufour’s gas business, assuming that Whiddon would not be a competitor for six more years. Dufour sold all of the assets to Herring, keeping the actual corporation “Gaston’s LP Gas Co.” for himself. What mistake in drafting have Dufour and Herring made?