Fifteen-time Grammy Award winner Adele has announced the cancellation of the last two shows of what could be her last world tour with a heartfelt letter she posted on Instagram.

The singer said she had struggled for ways to ensure she could perform, maxing out on steroids and vocal aids, and even considering miming.

“To say I’m heart broken would be a complete understatement,” the singer said in the letter, apologizing again and again to her fans for the disappointment.

She has said that refunds will be available for ticket holders if the shows are unable to be rescheduled.

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