My iPhone 11 Pro is stuck on 3G when I know I’m on a 4G area

Hey everyone ever since I did this update today my iPhone 11 pro is stuck on 3G when I know I’m on a 4g area and other iPhones not sure on models are on 4g is there a fix for this?

also is any one else Experiencing dropped our phone calls?

[Re-Titled by Moderator]