Harry Styles is still a huge fan of his ex-girlfriend Taylor Swift’s music.

The One Direction star couldn’t resist singing a tiny bit of Swift’s “22” after realizing it was an audience member’s birthday at his One Night Only gig in London, U.K. Tuesday.

He sang into the microphone, “I’m feeling 22, ooh ooh!”

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Styles and Swift famously dated back in 2012 before breaking up in 2013.

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They’re thought to have written songs about one another; Styles’ “Two Ghosts” and Swift’s aptly named single “Style”.

Howard Stern even commented on the duo’s brief romance as Styles promoted his new album Harry’s House on his show recently.

Stern noticed Styles had an album track called “Daylight” and wondered if it was a reference to Swift’s song of the same name on her 2019 album Lover.

Styles insisted it wasn’t, telling the host: “You know I’d love to tell you you’re spot-on, but you’re not.”