I fixed mine by downgrading with a pc. Follow this guide https://www.youtube.com/watch?v=NA01bacI5Vg. Once its done you'll be on android 11.If the link gets deleted or something just lookup How To Unbrick The Asus ROG Phone 3 from the channel GEEK...
Same for me. I just got an email from my phone service provider and I need volte or I wont be able to make calls anymore, and since volte is disabled in android 12, I need to downgrade very urgently.
