Chappell was in high demand and the
Primavera festival director was not going to accept "no" as an answer.

"Chappell Roan’s booking was a saga of its own. “Chappell wasn’t touring and it was the director of the festival — he had been saying, ‘We need her. I want her,’” Marta recalled. “And at one point he said, speaking to the booking department, ‘I don’t care if you have to get on a boat with fishermen in Norway and get to an island where she’s staying and get her out of retirement. I want her.’

“It wasn’t Norway, it was London. Two members of the booking department went there and spoke to her. And she said, ‘You’re telling me you have Sabrina and you have Charli?’” The result? A sell-out event before Christmas. "

https://www.standard.co.uk/showbiz/charli-xcx-sabrina-carpenter-chappell-roan-primavera-sound-b1231753.html