Hello & Welcome to Just Answer,
Sorry to hear of the issue you are having with your phones.
May I ask:
1) How many TOTAL handsets do you have with this system?2) What phone service provider (phone company) you have for this phone line?3) If you have ANY other devices (phones, fax, alarm system, etc.) attached to this same phone line (not part of the cordless system)?
4) Are you seeing an "in use" message - when trying to use any of the handsets?
I didn't see a response to my initial questions, but I do have a link to the manual for this system below.
Also, for MOST operations, pressing the OFF button on all handsets should turn OFF any "conference call" mode that has been established.
Now if your handset(s) are showing "in use" when you try to make a call, there could be other issues - which is why I asked most of the first questions.
Please let me know if you have any more issues, questions, or details for me so that we can continue to find the real issue here.
Thanks, ***** *****
I see it has been a few days and I just wanted to follow up to see if you have any more questions concerning this issue or if the issue was resolved.
I look forward to any further questions or results that you may have.