Article continues below advertisementJennifer Lopez turned her Up All Night show in Warsaw, Poland, into a spectacle after her skirt fell off her waist in front of 70,000 fans.The entertainer was backstage changing her outfit between songs when her associate invited the band back out to sing "Happy Birthday" to Lopez, who celebrated her 56th birthday one day before her performance on July 25. As the "On The Floor" singer rushed back to the stage for the audience to sing, a member of her team attempted to fasten her fringed gold skirt - but to no avail.