See above fixes from the BETA VERSION issue where users lost Siri and Dictation, the same issue is still happening on ios16 16.0.3 !!! You wont have to wipe/reset everything, thankfully I found the above fix before resorting to reset all! (i have an iPhone 12 mini)

THANK YOU!! I have the public ios16 on my iphone 12 mini. I suddenly lost dictation and Siri...after a week+ of ios16 working fine.. this random setting switch fixed it!!!! so glad I don't have to reset the phone!!