K-On! is not a band, so of course, it doesn't exist.https://en.m.wikipedia.org/wiki/K-On
K-On! (けいおん!, Keion!) is a Japanese four-panel comic strip seinen manga written and illustrated by Kakifly. The manga was serialized in Houbunsha's manga magazine Manga Time Kirara between the May 2007 and October 2010 issues. It was also serialized in Houbunsha's magazine Manga Time Kirara Carat. The manga relaunched from April 2011 to June 2012 with two separate storylines published in Manga Time Kirara and Manga Time Kirara Carat. The manga is licensed in North America by Yen Press. A spin-off manga about a different band of high school girls, K-On! Shuffle, began serialization in July 2018.
The anime studio which made the anime was fired last year.https://en.m.wikipedia.org/wiki/Kyoto_Animation...
The Kyoto Animation arson attack (Japanese: 京都アニメーション放火事件, Hepburn: Kyōto Animēshon hōka jiken) occurred at Kyoto Animation's Studio 1 building in the Fushimi ward of Kyoto, Japan, on the morning of 18 July 2019. The arson killed at least 36 people, injured an additional 33, and destroyed most of the materials and computers in Studio 1.
What are you talking about?