Among the performers celebrating Friday’s inauguration of President Donald Trump was Utah-based quartet The Piano Guys, who performed a mash-up of “Amazing Grace” and country singer Rachel Platten’s “Fight Song”, the latter having somewhat ironically been used as a anthem at various Hillary Clinton campaign events last year.

Platten, who sang and co-wrote the song, was less than thrilled to see the tune associated with the incoming Commander in Chief, and expressed her displeasure on Twitter.

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“While I respect the office of the President and the peaceful transfer of power, I want to make clear that at no point did the Piano Guys ask for permission,” she writes, “nor did I or anyone on my team know of, approve or endorse their decision to play ‘Fight Song’ tonight.”

Platten wasn’t the only person upset over seeing a song used during the inauguration. Savan Kotecha, songwriter of One Direction’s hit “What Makes You Beautiful”, was likewise shocked to hear the Piano Guys play his song during Inaugural Ball, and is so upset he’s even hinting at taking legal over it.

Following their performance — and the ensuing barrage of tweets from disgruntled songwriters — the Piano Guys responded via Twitter, stating that they simply loved Platten’s song, which “had nothing to do with Hillary Clinton or politics” and confirming they did not receive Platten’s endorsement.