N-Dubz have apologised to angry fans after the band cancelled a performance five minutes before they were due on stage.
The support acts had already appeared at the concert at Nottingham's Motorpoint arena on Tuesday 22 November and 35-year-old rapper and singer star Dappy Contostavlos had shared on social media that he was feeling unwell.
An announcement was made in the arena at 9.05pm telling concertgoers: "We are sorry to announce that due to artist illness, tonight's performance has been postpone and will be rescheduled.
"We understand the frustration and inconvenience caused by this late announcement; however. it is just not possible for the artists to go ahead this evening."
N-Dubz have now issued a statement saying: "We’re so sorry we had to cancel the show. We tried to do everything possible to make the show happen, but a doctor advised at the very last minute that Dappy was unable to perform and needed to rest tonight.
"We had to take this advice seriously and consider Dappy’s health so that the rest of the tour can happen, which has so far has been amazing.
"The O2 Arena show (November 23) and the rest of the tour will still be going ahead. We will make a further statement after Dappy has seen the doctor again tomorrow morning.
"We’re deeply sorry to all the fans who travelled to see us tonight and promise to make it up to you with a new rescheduled date for the show. Dappy, Tulisa & Fazer."
Dappy had shared on his Instagram stories a video of himself lying in bed in a tour bus.
He wrote: "Too many shows back to back with no proper breaks, now I'm completely f***ed. Voice basically gone, flu chest infection etc..."
He added: "Voice is fully gone now, I'm so sorry Nottingham."
Many fans shared their anger on social media.
One tweeted: "Doors open at 6pm and they waited till past 9pm too cancel the concert, knowing full well they weren’t gonna be coming on Money before customers once again from Nottingham motor-point arena….wait for everyone buy the beer and food before cancelling #ndubz #nottinghampointarena"
Another said: "#NDubz was ridiculous tonight. 5 minutes AFTER they were due to start they cancelled. After a hellish journey there too - Nottingham Motorpoint Arena is not set up for big gigs clearly. Fuming"
And another fumed: "Why let the support acts preform if you knew it wasn't going to go ahead? You knew Dappy wasn't well when he posted on his Instagram 4 hours ago "sorry Nottingham" so why only announce it 30 minutes before you're due to preform? Just poor! #Refund #Ndubz #noexcuse"
Their tour began in Newcastle on Monday 7 November and they had performed 11 shows in two weeks before cancelling the Nottingham show.
The tour is due to continue until 6 December and N-Dubz have just announced dates for a summer 2023 tour and an appearance at the Isle of Wight festival.
N-Dubz released their first single You Better Not Waste My Time in 2006, reaching 26 in the UK Singles Charts.
The band released three studio albums before parting ways with their record label Island in August 2011.
Tulisa teased a reunion in 2012 and Fazer - real name Richard Rawson - said the band were talking about reforming in 2017.
In 2013 Tulisa was arrested on suspicion of supplying Class A drugs, but the case was dismissed in 2014 because the judge believed prosecution witness Mazher Mahmood, an undercover reporter for The Sun newspaper, had lied in court.
Mahmood – known as the Fake Sheikh – was later jailed for tampering with evidence in Tulisa's drug trial.
Tulisa was convicted of assault in 2014 for hitting a celebrity blogger at a music festival a year earlier.
Dappy and Fazer are not without controversy themselves, having been escorted off a flight from Edinburgh to London by police in 2009 after allegedly threatening passengers.
And in 2010 the band apologised after Dappy sent a death threat to a BBC Radio 1 listener who had texted The Chris Moyles Show to say she thought the music star had a "silly hat" and the band were "losers.
After DJ Moyles read the text out on air Dappy copied the listener's phone number and sent her a threatening message.
Watch: N-Dubz announced their reunion tour after 11 years hiatus