Sam Smith has cancelled the last two dates on their U.K. tour after being advised to rest their voice.

The Unholy singer, who uses they/them pronouns, scrapped their show in Manchester, England after only four songs on Wednesday after they noticed "something wrong" with their voice.

On Thursday, they confirmed that they have had to cancel the last two shows on their U.K. tour in order to rest their voice.

"Due to vocal issues during last night's Manchester performance, regrettably we will be cancelling the rescheduled Birmingham and Glasgow Sam Smith shows," read an announcement on his Instagram Stories.

It continued, "A spokesperson said 'doctors have advised due to a vocal cord injury, Sam must have complete vocal rest. Sam is heartbroken to have had to cancel these shows but they have been told by doctors that if they keep singing, they will do permeant damage to their voice. If they take some rest they will be able to perform again.'"

The 31-year-old performer reassured their fans that refunds for the scrapped shows will be available.

Alongside the statement, Sam simply added, "I'm so sorry," with a heartbroken emoji.

The Stay With Me singer is next scheduled to perform in Warsaw, Poland on 3 June.