This page includes information and forms for modifying child support in an existing divorce, custody or parentage order. (Check this box and complete this section only if you are asking to change payment of child care.E90A Confirmation of Custody Change. Complete this form if we currently collect child support for you but the children are now living with someone else. Requests for review and adjustment must be made in writing. Use our child support modification form to update a child support agreement. Mail completed form to: Office of Recovery Services, PO Box 45033, Salt Lake City,. To modify a child support order, you may take one of two approaches: Filing a Motion to Modify Child Support or filing a Petition to Modify Child Support. How Can I Change My Child Support in Utah? A motion is often filed under limited circumstances in Utah, making the filing of a petition the better option in the majority of cases.