A bout of laryngitis forced Rihanna to cancel her planned concert in Boston on Sunday night.

The “Diamonds” singer was due to perform at the TD Garden, but promoter Live Nation postponed the show on Sunday morning, posting the following statement on Facebook: “Unfortunately, following her sold-out concert on Friday, Rihanna has contracted laryngitis and per doctor's instruction is unable to perform this evening."

Rihanna took to Twitter to send a message to her fans, saying, “#BOSTON this is the hardest thing for me to deal with! I feel like we've been waiting on this day forever, and I'm hurt that I let you down.” She later tweeted, “I hate disappointing people that never ever let me down!! I'm so embarrassed about this! Thank you for your prayers and well wishes! #DWT”

The date has yet to be rescheduled. Rihanna's expected back on stage this Tuesday in Baltimore. She kicked off the tour this past Friday in Buffalo, New York.