diff --git a/internal/sm2ec/p256_asm_arm64.s b/internal/sm2ec/p256_asm_arm64.s
index f649f91..adff710 100644
--- a/internal/sm2ec/p256_asm_arm64.s
+++ b/internal/sm2ec/p256_asm_arm64.s
@@ -82,8 +82,8 @@ TEXT ·p256BigToLittle(SB),NOSPLIT,$0
 
 	VLD1 (a_ptr), [V0.B16, V1.B16]
 
-	VEXT	$8, V0.B16, V0.B16, V2.B16
-	VEXT	$8, V1.B16, V1.B16, V3.B16
+	VEXT	$8, V0.B16, V0.B16, V3.B16
+	VEXT	$8, V1.B16, V1.B16, V2.B16
 	VREV64 V2.B16, V2.B16
 	VREV64 V3.B16, V3.B16