Jess Glynne has apologised to her fans after cancelling a number of gigs - including Forest Live - until mid-July due to a vocal haemorrhage.
She has cancelled her concerts at Sherwood Pines Forest Park, near Mansfield, this Friday June 28 as well as Cannock Chase Forest, near Rugeley, on Friday July 5.
The singer-songwriter recently pulled out of her Isle Of Wight Festival slot at the last minute earlier this month after supporting the Spice Girls on tour, said that cancelling her shows was a difficult decision.
Glynne was criticised by some fans for her absence from Isle Of Wight, which came after she partied until the early hours of the morning with the Spice Girls following their final concert at Wembley.
But she has now said her medical issues were present prior to the celebrations and she has been warned she could damage her voice permanently if she does not take time off.
Glynne, 29, said in a statement: "It absolutely kills me to say this - especially given what has happened in the past few weeks - but on the advice of my throat surgeon, I am going to have to cancel my next shows through until July 14 and I hope to be back as soon as possible after that.
"I know many of my fans feel I let them down so badly when I pulled out of the Isle Of Wight festival but the reason I knew I just wasn't going to be able to make that performance has now been made clear to me by my doctor, Dr Zeitels."
She said it is "true that that I went out and celebrated the end of the Spice tour".
"That was a massive high for me and I wanted to mark it with the women who'd become friends and mentors to me," she added.
"But I had also been suffering on and off for weeks with anxiety about my voice. It wasn't right. I wasn't sounding my best and I felt there was something wrong.
"Two days ago I came to Boston to see my surgeon who told me my vocal chord has haemorrhaged and that if I wanted to remain as a performer I needed to urgently take a break, rest my voice completely for the next 10 days and try and remain in total silence to give my vocal cords a chance to recover."
Glynne said she was told she was "completely overdoing everything" having performed nearly 100 shows over the past six months, and pushing through "at times when I know I've been tired and overstretched and I got to breaking point, my voice literally got to breaking point".
She said she is "devastated" to let people down but that she needs to focus on healing her voice, otherwise her career could come to an end.
Forest Live the concerts cannot be rescheduled.
"Ticket holders for the Forest Live performances will be contacted by their point of purchase to arrange a refund."
Glynne was due to perform across the UK through the end of June until mid-July, including at TRNSMT Festival in Glasgow, Dalby Forest in Pickering and Kew Gardens in Richmond-Upon-Thames.