Well, this is QUITE the accusation.
She shared a clip of the part the hitmaker stole, and called her out in the caption, writing:
[Image via Beyoncé/Marlyn Ortiz/Instagram.]
Nod your head to the SLICK beat of Lissie's drum and watch her LIVE version of Shameless (above)!
We still can't get over how mind-meltingly AWEsome and stuffed with diverse musical talent this year's shindig was!