Iowa Code § 455B.336
If the director determines that there are reasonable grounds to believe a violation of this part 2 of subchapter IV or of the rules issued under said part has occurred, the director shall give written notice by certified mail to the alleged violator specifying the alleged violations involved and specifying a period of time in which to eliminate the violation. If the alleged violator fails to comply within such specified time, the director shall schedule a hearing and give written notice to the alleged violator by certified mail. In connection with the hearings, the director may issue subpoenas requiring the attendance of witnesses and the production of records pertinent to such hearing. On the basis of the findings, the director shall issue a final order which shall be forwarded to the alleged violator by certified mail.
Iowa Code § 455B.336