Freya Ridings has pulled out of the Coronation Concert due to being unwell, according to reports.
Meanwhile, Zak Abel will now join the lineup consisting of Take That, Katy Perry and Lionel Richie.
Singer-songwriter Freya, 29, was set to take to the Windsor Castle stage on Sunday as part of this weekend's celebrations, as King Charles III and Queen Camilla are crowned.
Londoner Zak will now be filling in for Freya after being too unwell to perform.
He is set to showcase his soulful vocals in a duet with classical-soul composer and producer Alexis Ffrench at the historic event.
The star-studded concert will celebrate the Coronation of Their Majesties The King and Queen and will be broadcast from 8pm on BBC One, BBC iPlayer, Radio 2 and BBC Sounds on Sunday 7th May.
In a statement, the broadcaster said: “The BBC has announced that British singer-songwriter Zak Abel is stepping in to perform at Sunday’s Coronation Concert at Windsor Castle, replacing Freya Ridings, who has had to pull out, due to being unwell and therefore unable to perform."
Speaking of his last-minute addition to the lineup, Zak said: "I am honoured and overwhelmed to be included in the Coronation celebrations.
"To have the opportunity to be part of such a historic moment is something I will forever be humbled by and will never forget.”
The singer-songwriter signed his first record deal when he was a teenager.
Zak, 28, creates his own compositions which feature his instinctively soulful, funky and catchy melodies.
In his career so far, he has collaborated with some of the world’s biggest dance producers, including Kygo, Avicii and Tom Misch.
Zak was diagnosed with otosclerosis – overgrowth and brittleness of the stapes bone in the ear, which can lead to hearing loss – when he was just 21.
He has overcome a number of hurdles in order to achieve success in the world of music, which has led him to the opportunity to perform at this once-in-a-lifetime event.
The day before he is set to make his appearance on the Royal stage, Zak is performing in Berlin, Germany.
He is best known for tracks Freedom, Bad and Beautiful Escape.
Freya, 29, rose to prominence back in 2017 with her ballad, Lost Without You, which became a top ten hit on the UK Singles Chart.
The North London singer has two albums with her self-titled album being supported by the single Castles, which would become her international breakthrough.
The likes of Katy Perry and Lionel Richie are set to grace the stage and put on a performance to dazzle the Royal Family and the thousands of spectators in attendance.
Along with the aforementioned American Idol judges, other acts ready to woo the watching crowds around the world include Take That, Paloma Faith, Olly Murs, Steve Winwood, Nicole Scherzinger and Andrea Bocelli.
The concert will be hosted by actor Hugh Bonneville, Tom Cruise, Dame Joan Collins, Bear Grylls and Sir Tom Jones are all set to appear in special video messages.
However, the concert faced its challenges in the lead-up to the big day as many famous faces declined their invitations.
Icons Sir Elton John, Kylie Minogue and the Spice Girls were among those on a growing list of stars who won't be attending.
The Rocket Man won't be performing due to his European tour, which sees him performing in Germany the Friday before with not enough turnaround time blamed.
Ed Sheeran also had to say no due to "logistics and previous touring commitments" and a similar reasoning was said to be behind Adele's choice to say no.
The pair's rejection was reportedly a huge blow to organisers who had apparently placed the pair at the top of their wish list.
