45 CFR § 303.35 - Administrative complaint procedure.
(a) Each State must have in place an administrative complaint procedure, defined by the State, in place to allow individuals the opportunity to request an administrative review, and take appropriate action when there is evidence that an error has occurred or an action should have been taken on their case. This includes both individuals in the State and individuals from other States.
(b) A State need not establish a formal hearing process but must have clear procedures in place. The State must notify individuals of the procedures, make them available for recipients of IV-D services to use when requesting such a review, and use them for notifying recipients of the results of the review and any actions taken.