This Morning's Dermot O'Leary was corrected by his co-host Alison Hammond after he made a blunder on the ITV magazine show.
During a segment teaching women how to embrace their wavy hair, Dermot complimented Alison's curls.
Not realising that it was fake hair, he asked how she achieved the look.
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"You have some lovely curls," he admired.
And Alison thanked him on his compliment as she shook her springy tresses.
But then Dermot continued: "What do you do with them?"
"What do you mean what do I do with them?" she asked.
"How do you make them so curly?" he wondered.
"It's fake hair," she said incredulously.
"Well it's sensational," he told her as Alison laughed at his mistake.
She explained to her co-host: "This is a protective hairstyle.
"When I want to protect my hair for a while I braid my hair underneath and then I attach these to it.
"It's not my real hair, it's synthetic."
And Dermot said: "Incredible. You learn something new every day."
Viewers commented on social media about the moment.
"I loved watching this on the TV made me smile always good to educate yourself," said one.
"Awww Dermot - bless him," said another.
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"Oh Dermot you have a lot to learn son," wrote another.
Others praised down-to-earth Alison on her handling of the mistake.
"Keeping it real as always," said one.
"Love it, always brighten my day," another wrote.
"Lol nothing held back with Alison," said another.
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