I’m thankful I found this post. When this bug originally happened to me, I was running iOS 16 public beta three, and I thought it was just a beta bug. When it stuck around after iOS 16 was officially released I thought it must be a leftover bug from the beta. I did a clean restore with iOS 16, and that fixed Siri and dictation. At some point it stopped working again and I didn’t know what to do. After finding this thread, I changed Siri‘s language in my keyboard to English UK, and everything was working! I did find it inconvenient that American spellings of words were coming up as spelled wrong, and I found that dictation was not as good for whatever reason. I had UK set for a few days when I saw a comment on this thread about disabling VPNs. I use a VPN as an ad blocker, and I wondered if that was causing any issues. I disable the VPN and switched back to English US and everything was working again! I enabled the VPN and everything was still working. That was two or three days ago, and everything has been working as it should. I dictated this entire post (16.0.2). I’m not a developer, but if I had to guess, I’d say it wasn’t the VPN and had more to do with me being on UK for long enough for English US to maybe be deleted and re-download? I’d also be interested if others in this thread either we’re on the public beta or use a VPN.