It is against the law for a bill collector who works for a collection agency to call you at an unreasonable time. If collection agencies have been calling you at all hours of the day and night, you can get them to stop contacting you. The law says that calls before 8 a.m. or after 9 p.m. are unreasonable. Other times may be unreasonable, too, such as during daytime hours if someone works at night. If collectors are calling you at work, harassing you, using abusive language, making false or misleading statements or adding unauthorized charges, under the Fair Debt Collection Practices Act, you can demand that the collection agency stop contacting you except to tell you that collection efforts have ended or that the creditor or collection agency will sue you.