Here's the deal ... the Grammys don't start until 5 PM PT, but before the ceremony, the Recording Academy uses its X account to hand out some of the trophies -- basically to cut down time during the ceremony.

One of those awards ... Best Rap Song, which was won by Nicki Minaj and Ice Spice for their song "Barbie World" -- a huge moment for the rappers -- except it didn't last 'cause the Academy seemingly took it back.

You see ... the Recording Academy deleted that congratulatory tweet and posted a different one -- saying Killer Mike had actually won the trophy for his track "Scientists & Engineers" featuring André 3000, Future, and Eryn Allen Kane.

Multiple outlets are reporting KM as the real winner of the Gramophone... so it seems NM and IS are officially out of luck!

Nicki's been through this song and dance before ... she's now racked up 12 nominations without taking home a single one. She was also nominated for Best Song Written for Visual Media -- but lost that one to Billie Eilish and FINNEAS for "What Was I Made For?" When it rains, it pours!

But if anyone's taking it harder than Nicki ... it's the Barbz -- who think the whole damn ceremony is rigged.

In fact, they're so sure about this they've got #Scammys and #BarbieWorld trending on X ... basically claiming the Academy rigged the results because of Nicki's explosive beef with Megan Thee Stallion.

So is there some kinda of grand conspiracy going on, or just an honest mistake from the Recording Academy's social media manager? Let us know below.