I think today's 9.01 update corrected some of the SIRI issues. Hey siri stop working for me after the 9.0 and OS2 updates. I installed 9.01 on the phone and rebooted both the watch and the phone by holding the crown and the other button down until the watch turned off. Did the same with the phone by holding the menu button and on off switch down until the phone turned off. after restarting both my siri issues were corrected.
This re-boot method is not just holding the off button and then sliding the device to off. That only shuts the device off. The holding down of both buttons re-boots the device which can clear file issues.