Rachel Platten is the latest songwriter to speak out against the unauthorized use of music at Donald Trump's inaugural ball (January 20).

On Friday, the chart-topping musician and singer expressed her frustration over The Piano Guys' unauthorized cover of her inspirational hit single, "Fight Song," which the YouTube artists performed in a mash-up with "Amazing Grace."

Platten revealed that the song was never cleared for use at Trump's inauguration ball—in fact, the empowering track was actually used as an anthem for Hillary Clinton's campaign during multiple rallies in 2016—writing on Twitter, "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, nor did I or anyone on my team know of, approve or endorse their decision to play 'Fight Song' tonight."

In response, The Piano Guys confirmed that while their mash-up performance was, indeed, not endorsed or approved by Platten, their cover "had nothing to do with Hillary Clinton or politics."

"We love Rachel and we love her song," the group added via Twitter.

Ironically, Platten's song was not the only track covered by the band without permission from its original songwriter.

One Direction songwriter Savan Kotecha shared on Twitter that The Piano Guys' performance of "What Makes You Beautiful," a song he said was written to celebrate "love, joy and acceptance," was similarly not cleared for use at Trump's ball.

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