cannot make 3-way or merge calls
"Could not save call waiting setting" then a button to Dismiss.
No idea why it's happening... my husband's phone it works and we're on the same plan. This means I can't answer call waiting, can't make a 3 way call, can't merge 2 calls, etc. I'm assuming I'll have to call AT&T to rectify the situation, but any ideas or is this happening to anyone else?
iMac, Mac OS X (10.4.7)