Had the same issue. Several restarted did not fix it by: switching back to United States English from British, then turning Siri off, all hey siri, listen, tap to talk settings off as well restarting iphone Toggling settings back on Going back to desired Siri language (I believe only English is supported for beta Siri to work As of devbeta 1) Opening Siri app (this forced an update and restored functionality and my conversations.)