Golden and his family run a family farm in Iowa. The farm had severe financial problems, and Golden was forced to assign a large portion of his income to creditors for several years. Goldens brother and father both died from cancer, and Golden agreed to pay medical expenses for each. The Mayo Clinic was owed $1,000 by Golden for medical treatments for his brother and father. Mayo has a long-standing policy of not charging interest on debts owed. Mayo authorized ABC Collections to pursue payment of the principal amount only. ABC representatives called Goldens home numerous times during a day for several weeks. Some of the conversations became heated, with ABC Collections representatives threatening Golden and calling him a deadbeat. ABC finally sued for both the principal and interest. What act may be violated? Why?