Singer IU apologizes to IVE, whom she met for the first time, saying ”I'm sorry”... Why?

Singer IU has apologized to her junior group IVE. On the 20th, IU's YouTube channel "Ijigeum" posted a "wrap-up party with the IVE family."
"IU and IVE both use the same shop, but this is the first time they have met or spoken to each other," he explained.
IU then began by saying, "There's a story behind us," and explained, "Originally, we were looking for the members of IVE (companies).
"I wanted to invite you to the new album (the title of the album is "Palette") as soon as possible. I had planned to invite you," he said, "but I would like to take this opportunity to apologize once again," he said, bowing 90 degrees and apologizing.
The shocked IVE members also jumped up and shook their heads, saying, "No." IU emphasized, "I'm really sorry," but IVE's Jang Won Young said, "We
I always hoped that my senior would never think like that." It was later revealed that the record was postponed from the originally scheduled date due to IU's poor health.
IU continued, "When I was recording 'Palette,' something like that happened to me for the first time. It was the day we were supposed to record, but it just happened and I felt something was wrong.
He had a really high fever, so we had to cancel the record that day to go to the hospital. I felt really sorry about that, and the staff at the shop were really sorry too.
IU then said, "I took off my hat and mask and said, 'I'm sorry, I'm so sorry. I'm ...
"But," he said, "I'm really sorry, please convey that to the members of IVE again. That's the thing I've fallen short of the most in 2024."
However, the IVE members again unanimously said, "No!" and Jang Won Young said, "We really need to get better soon.
"I just wanted to say, 'I want to be your boyfriend,'" she said, waving her hand. IU expressed her regret and pain, saying, "Hearing that he said that made my heart ache even more."
IU said, "I know how busy you are, arranging my songs, preparing Color Switch, and taking time out of your day for 'Palette.'
Today, I will do my best to welcome you all with a bright and cheerful attitude, even including the mistakes of the day. I would like to thank you once again for appearing on ‘Palette.’”
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