In Simonds v. State, 799 P.2d 1210, 1215 (Wyo. 1990), the Court did not remand for resentencing on all issues. The district court in Simonds, therefore, could not alter the rms with respect to the sentence that had been affirmed. In Simonds, the Court remanded for resentencing on only one of two charges, but the district court changed Simonds' sentences from concurrent to consecutive terms. Simonds, 799 P.2d at 1211. The Court held that such a change constituted an increased sentence and violated due process. Id. at 1216. The Court stated: "We have held that, following a remand by this court, the district court is bound to substantially comply with our mandate. Accordingly, it has the jurisdictional authority to determine only those issues expressly directed by the mandate and such previously undecided collateral questions as are necessary to reach a decision on the mandated issues. The district court is without the authority to alter its former decision with respect to matters affirmed, and thus finalized, by the mandate."