Fans of the band Beach House became excited last month when a new advertisement for Volkswagen was broadcast in Britain. The spot tells the story of a father raising his daughter and featured what sounded like a new song by the Baltimore duo.

The only trouble was, it was not a Beach House song — it just sounded like one to fans. Beach House — the duo of Alex Scally and Victoria Legrand — had repeatedly turned down lucrative offers from Volkwagen and DDB, its ad agency, which sought permission to use the 2010 song “Take Care” in the ad. When Mr. Scally started hearing from fans about the commercial, he said he rushed to find a copy online.

“It was a crazy moment,” Mr. Scally said by telephone while on tour in France. “We didn’t give them the song, and they made a very similar song to replace it.”

He added: “The worst thing is that it feels like something close to what we made. A feeling and a sentiment and an energy has been copied and is being used to sell something we didn’t want to sell.”