Blake Shelton still doesn't recognize some of Gwen Stefani's music after nearly four years together, but as it turns out, that's perfectly fine with the pop superstar.

Shelton was appearing on the Tonight Show Starring Jimmy Fallon in October of 2018 when he participated in a game of "Name That Song." The sketch features Fallon's house band, the Roots, playing a song one instrument at a time while the players all guess the song. Shelton failed to recognize Stefani's "Hollaback Girl," which became a hit all over the world and reached No. 1 on Billboard's Hot 100 in the U.S. after she released it as the third single from her debut solo album, Love.Angel.Music.Baby, in 2005.

"I came to this show to promote my album and I'm losing everything! Everything in my life," Shelton lamented comically after the embarrassing incident.

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Fallon asked Stefani about it when she appeared on the show on Monday (Sept. 23) to promote her recent Las Vegas residency, and she just laughed it off.

"That is so funny," she said with a broad grin. "He should have known that one, but he's country. He doesn't listen to that."

Stefani has recently returned to The Voice for Season 17 to fill the empty seat Adam Levine's unexpected departure left, joining coaches Shelton, John Legend and Kelly Clarkson to battle it out to find the next big singing star.

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