Adele stunned fans who had travelled to Las Vegas before her residency was cancelled as she called them on FaceTime.
The Hold On singer broke down as she offered her "apologies to fans" who had travelled to see the opening night of residency in Sin City.
She said: "I've shows in the UK this year, and I hope we can get together then," she added.
"I do not want anyone to miss out. I just want to send my love to all those who have been left disappointed. From the bottom of my heart I am sorry."
She held several weepy and heartfelt conversations, leaving some supporters in floods of tears.
Student Amiah Shaw, 19, from San Francisco, was one of the lucky ones to speak directly to the star.
She said: "Adele has been in my life from a very young age.
"She is everything to me.
"The disappointment of not seeing her perform was heartbreaking, but to be able to speak directly to her and be reassured she is ok is priceless.
"She promised she will be back to see us, and I know she will.
"I love Adele."
About 50 of her loyal fans, known as Daydreamers, held a sing-a-long of the star's hits at the entrance of the Colosseum at the moment she should have taken to the stage.
Several US ticket holders suffered further disappointment after believing a conspiracy theory she would still show up.
Despite holding a "vigil", Adele failed to appear in person instead opting to speak to them through a friend's iPhone.
Many, even some of her loyalist fans, have questioned if the shows will now ever go ahead.
Teresa Whittle, 42, from Detroit, Michigan, expressed her concerns as she shopped for some of Adele's residency merchandise.
She said: "I think we all know how fragile she can be.
"Adele is a perfectionist, but what comes with that are incredible nerves about not getting it right every time.
"She clearly struggles with that sometimes to the point it seems to cripple her.
"I hope she reschedules all her shows, but it would also not surprise if her residency never happens.
"Things like this can have a massive impact on performers - some never come back from it.
"I hope she does."
The residency's postponement sparked fury among many, demanding she refunds the money they had laid out given how little short notice she provided.
In her video message posted on Instagram, a teary Adele said: "I'm so sorry, but my show ain't ready.
"We've tried absolutely everything that we can to pull it together in time and for it to be good enough for you, but we've been absolutely destroyed by delivery delays and COVID," she said, adding that "half my team are down with" the virus.
She had been due to perform 24 shows at Caesars Palace Hotel starting Friday following the release of her fourth album, "30."
Caesars Palace said it understood fans' disappointment in a tweet but added: "Creating a show of this magnitude is incredibly complex. We fully support Adele and are confident the show she unveils at The Colosseum at Caesars Palace will be extraordinary."
No timeline has yet been given when fans can expect the shows to begin.