The machine is clearly broken.
First of all, Nmixx. Complete revamp. Give them remakes of WG or Miss A songs, like SM with Aespa did. Nostalgia works wonders and you clearly have problem with getting new hits. So it is pointless to keep trying.
Twice. Instead of doing all those billboards and other big promotions for Ready To Be they should focus on existing Twice content, which is a lot. Playlist Fancy, Cry For Me, much as you can internationally and couple of other songs. Do Tiktok remixes like Lady Gaga's Bloody Mary and things like that. Twice has Bsides that could explode any moment. Korea is still largely unaware of songs like Cry For Me for example, they should promote it somehow.
Start promoting Itzy individually. Send them on varieties, shows, promote their individual brand. And then when they are established, then give them comeback. It is absolutely stupid that Yuna isn't as hot as Wonyoung or Karina right now.