If it’s up, then it’s up, then it’s up, then it’s stuck.

Cardi B let her tampon string hang out while she gyrated onstage during a commando performance in Las Vegas last Friday.

The “WAP” rapper, who was wearing a gold-fringe minidress, showed the crowd of attendees at Drai’s Nightclub more than just her dancing skills when she approached the front of the stage.

In a video recorded by a horrified concertgoer, Cardi was seen patting her lady parts as she moved her hips in a circular motion.

Within seconds of the sultry solo, it became obvious that the married mother of two was not wearing any underwear.

However, she was wearing a disposable menstrual product, whose long white thread flailed about in unison with her swaying lower body.

It wasn’t just the panties Cardi ditched; she was barefoot, too.

At another point during the night, after she finished belting out her final song, “I Like It,” the Grammy winner, 30, chucked her microphone in the direction of the DJ booth.

Though she did not say anything before or after the throw, Cardi appeared angry as she exited the stage alongside her bodyguards.

Social media users have speculated that she was mad at the DJ for continuously cutting her tracks short during the set.

The hip-hop hitmaker has already made headlines for a different mic toss during the same weekend.

While performing “Bodak Yellow” at Drai’s Beachclub on Saturday, the New York native encouraged fans to “splash” water “in [her] p—y.”

The request seemingly led someone in the first few rows to hurl their open drink at the musician, which prompted a shocked Cardi to fling her mic with force into the area from where the beverage came.

A video of the altercation showed Cardi then shouting some inaudible words at the perpetrator before security swooped in to escort them out of the event.Page Six has since learned that the woman Cardi struck went to the Las Vegas Metro Police Department to report the incident.

Though cops told us no arrests or citations had been issued, TMZ claimed the singer was named as a suspect in a battery investigation.

Her reps did not immediately respond to our request for comment.