Isn't it plain error for a court to impose multiple punishments for multiple counts of conviction that for double jeopardy purposes amount to the same offense of conviction?

QUESTION PRESENTED Petitioner was convicted of, infer alia, six counts of conspiring to engage in the extortionate collection of credit. The first such count covered nearly a two-year period. The remaining five counts covered time-periods subsumed within that same two-year period with each count relating to a particular victim. Under Double Jeopardy principles, petitioners’ convictions on these smaller conspiracy counts should have merged with the overarching conspiracy count. The Second Circuit rejected petitioner’s merger argument because he failed to raise it in the district court and having received concurrent sentences held that there was no “obvious injustice in not reaching the claim.” United States v. Gershman, 31 F.4th 80 (2d Cir. 2022). In so holding, the Second Circuit necessarily rejected this Court’s view that even where a defendant “did not challenge the assessment below” on double jeopardy grounds such an assessment constitutes an impermissible collateral consequence and as a result any such additional conviction, ““as well as its concurrent sentence, is unauthorized punishment for a separate offense’ and must be vacated.” Rutledge v. United States, 517 U.S. 292, 301 (2006). A view shared by numerous other appellate courts permitting a defendant to “raise claims about the multiplicity of sentences for the first time on appeal.” United States v. Reedy, 304 F.3d 358, 364 (5th Cir. 2002) This petition raises the following questions: Isn’t it plain error for a court to impose multiple punishments for multiple counts of conviction that for double jeopardy purposes amount to the same offense of conviction? i