The Department shall investigate a complaint alleging that a business is:operating without a license; operating with improper licensure; or violating the terms of a business license; or engaging in unfair, abusive, or deceptive trade practices. If a complaint is not within the jurisdiction of the Department under subsection (a) of this section, the Department shall dismiss the complaint and, if appropriate, refer the complaint to another entity with jurisdiction over the matter. If a complaint is dismissed under this subsection, the Department shall promptly notify the complainant and respondent. Upon receipt or issuance of a complaint, the Department shall promptly investigate the complaint. In the course of an investigation, the Department may issue a subpoena to require any person to:produce information, documents, reports, records, accounts, or any other evidence related to the allegations in the complaint; and appear under oath to give testimony related to the allegations in the complaint. The Director may administer oaths as permitted under this section. The Department shall prepare a written report of findings as soon as practicable after the conclusion of the investigation.