Serena Williams chose to sit out on Sunday as some of the biggest names in tennis came together to celebrate the Centre Court centenary celebrations at Wimbledon. Williams, who lost in the first round at Wimbledon on June 29, skipped the centenary ceremony because she was frustrated after officials allegedly forced her to return her five courtesy cars shortly after she was eliminated from the tournament.

According to Yahoo Sports, Wimbledon requires players to return the courtesy cars within 24 hours after they’re eliminated. A Wimbledon source said Williams, who wanted to use the five cars for herself, her husband, sister, mother and coach, was hoping to keep the vehicles until the end of the tournament.

“She wanted to use the cars for the whole two weeks because that’s what happens at the other grand slams,” the source told Yahoo Sports. “She was told that was not possible because they had to be used by the other players. She was not happy. Maybe that’s why she refused to take part in the centenary parade.”

Wimbledon typically allows players to use a single car, but some stars are given additional cars for their coach. Roger Federer is believed to be one of the few players who has been allowed to use five cars when he is competing.

Federer joined tennis legends such as Rod Laver, Billie Jean King and Rafael Nadal as Wimbledon’s Centre Court celebrated its 100-year birthday, Telegraph reports. On the same day, Williams and her husband, Alexis Ohanian, attended the Rolling Stones concert at Hyde Park in London.

The tennis star hasn’t publicly commented on the dispute with Wimbledon officials. However, a Wimbledon spokesman who spoke with Yahoo Sports said “we have fulfilled every transport request we received.”