Within fifteen calendar days after the identification of a default under a support order, the office of child support in the department of job and family services shall send a default notice to the obligor. The default notice shall include a summary of the actions that may be taken against the obligor if the court or agency makes a final and enforceable determination that the obligor is in default. If the location of the obligor is unknown at the time of the identification of a default under the support order, the office shall send the default notice to the obligor’s last known address.