According to a report in Star magazine, the 24-year-old actress hates that her costar Shay Mitchell is getting more attention.
"She can't handle Shay being more important than her, so she's simply stopped speaking to her," the mag claims.
They also say Lucy's "bad attitude" is a problem and she's threatening to quit the show.
But a production source tells GossipCop this is "so not true."
And even Lucy herself took to Twitter to set the record straight yesterday.
"For the magazine claiming I am quitting Pretty Little Liars...that is absolutely false. I love the show and everyone involved," she Tweeted Wednesday afternoon.
Last year, Shay told Cambio that there's never drama on set, saying: "We all get along so well."
Good to hear the ABC Family series stars are here to stay!