Leron Michael Alexander appeals from his conviction of three counts of bank robbery, one count of carjacking, and four counts of using, carrying, or brandishing a firearm during a crime of violence. Alexander contends that the two firearm charges arising from the June 18, 2001, carjacking and bank robbery he committed should have resulted in one firearm sentence under 18 U.S.C. § 924(c) because the predicate offenses were grouped under the Sentencing Guidelines and because the carjacking and bank robbery occurred nearly simultaneously. He also argues that the district court erred by adjusting his guideline sentencing level as to one of his bank robberies because one of his victims was a vulnerable victim.

The evidence showed that Alexander brandished a firearm when he eommitted his carjacking offense, then again when he robbed the bank. Therefore, Alexander used a firearm twice to commit two different predicate offenses, carjacking and bank robbery. There were thus two units of prosecution, see United States v. Phipps, 319 F.3d 177, 186 (5th Cir. 2003), and § 924(c) authorized separate convictions and sentences. See id.

We need not address whether the vulnerable victim adjustment was erroneous. Without the adjustment, Alexander’s combined offense level for his multiple offenses would have remained 28, see U.S.S.G. § 3A1.4(a), and his total offense level would have remained the same. Any error regarding the vulnerable victim adjustment is thus harmless. See United States v. Sidhu, 130 F.3d 644, 652 (5th Cir. 1997).

AFFIRMED.