Guillermo Enriquez-Velasquez appeals his sentence of twenty-seven months, imposed following his guilty plea for illegal re-entry, in violation of 8 U.S.C. § 1326(b)(2). On appeal, he challenges his sentence in light of United States v. Book er, — U.S. -, 125 S.Ct. 738, 161 L.Ed.2d 621 (2005). Because EnriquezVelasquez preserved this issue, we review the sentence de novo and we reverse only if the error was not harmless. United States v. Paz, 405 F.3d 946, 948 (11th Cir. 2005).

After a review of the record, we hold that there was no constitutional error in sentencing because enhancement based on prior convictions under U.S.S.G. § 2L1.2(b)(l)(B) do not implicate the Sixth Amendment. United States v. Orduno-Mireles, 405 F.3d 960, 962-63 (11th Cir. 2005).

The government correctly concedes, however, that there was a statutory error in the imposition of the sentencing guidelines as mandatory. It is the government’s burden to show that this error was harmless, and the government admits that it cannot meet its burden in this case. United States v. Mathenia, 409 F.3d 1289, 1291-92 (11th Cir. 2005). The record is devoid of any evidence that Enriquez-Ve *244 lasquez’s substantial rights were unaffected by the sentencing scheme.

Accordingly, we VACATE the sentence and grant the government’s motion to REMAND for resentencing under an advisory guidelines scheme.