You will need to reboot the phone with the EHS unplugged.
Here are instructions on how to reboot your Polycom phone.
This should get it back into sync so that turning on the headset answers the phone, and turning it off ends the call.
Hi, I'm Kyle!
I manage this blog. Feedback, comments, compliments, criticisms, or any other questions? I'll take them all!
Kyle Newgent
Headset Blogger
(415) 351-5857
kyle@headsets.com