Hello & Welcome to Just Answer,
I'm Greg and will do my best to assist you today.
Sorry I didn't see your question earlier and to hear of any issue you are having with your phones.
If you still need help you with this issue:
If you are seeing "PRIV" on your phones, it means that you have "Call Sharing" turned OFF. This effectively prevents other handsets for joining in a call.
To turn ON Call Sharing", do the following steps on ANY HANDSET in the system - while the system is NOT in use (not on a call).
1) Pick up any cordless handset.
2) Press MENU # 1 9 4 (pound-one-nine-four). This is the "direct command" for the Call Share feature.
3) Press the UP or DOWN arrows to highlight the desired setting (ON in this case).
3) Press the SAVE button (or soft key - so save the selection).
4) Press the OFF button (to exit programming).
That should do it. If done correctly, any other handset should be able to "join" an ongoing conversation by pressing the TALK (or SP-PHONE) button.
Please give that a try and let me know your results - or if you have more questions.
If this has helped answer your question(s), please take a moment to rate MY service level (5-star is my goal) so that I get credit for my time helping you with this question.
You should see some "stars" (and SUBMIT button) to do that, but please let me know if you do NOT see them (you may have to REFRESH your screen) or can not use them.
Thanks, ***** *****