MEMORANDUM **

Raul Amezcua appeals from the district court’s order denying his motion for a sentence reduction under 18 U.S.C. § 3582(c)(2). We have jurisdiction under 28 U.S.C. § 1291, and we affirm.

Amezcua contends that he is entitled to a sentence reduction under Amendment 782 to the Sentencing Guidelines. We review de novo whether a district court had authority to modify a sentence under section 3582(c)(2). See United States v. Leniear, 574 F.3d 668, 672 (9th Cir. 2009). The district court correctly concluded that Amezcua is ineligible for a sentence reduction because Amendment 782 did not lower his applicable sentencing range. See 18 U.S.C. § 3582(c)(2); Leniear, 574 F.3d at 673-74. Because the district court lacked authority to reduce Amezcua’s sentence, it had no cause to consider the 18 U.S.C. § 3553(a) factors. See Dillon v. United States, 560 U.S. 817, 826-27, 130 S.Ct. 2683, 177 L.Ed.2d 271 (2010). Moreover, contrary to Amézcua’s contention, Booker did not give the court authority to lower Amezcua’s sentence. See Dillon, 560 U.S. at 828, 130 S.Ct. 2683 (proceedings under section 3582(c)(2) “do not implicate the interests identified in Booker”). Finally, Amezcua’s challenge to the form of methamphetamine involved in his offense is not cognizable in a section 3582(c)(2) proceeding. See id. at 826, 130 S.Ct. 2683 (section 3582(c)(2) does not authorize a “plenary resentencing proceeding”).

AFFIRMED.