Within the last 2 days my call waiting is not working on my iPhone 4S. I am talking on the phone (rare these days, I know) and the chime sound comes in that someone else is calling me. I look at the screen and nothing is displayed and the toggle (switch) button to answer the other line does not display. The calls where from contacts that I have on my phone. I checked My Features online at my Verizon and it is still listed as a feature for my line. (I just switched to Shared plan From Grandfathered Unlimited two days before this problem started.
This is definitely an odd situation considering you've got the call waiting feature attached to your line yet your screen is not acting like it. Well, I say we jump into the deep end and get this fixed ASAP.
To start, have you tried simply turning off your phone and then back on? Sometimes a simple power cycle will resync your device with our network so as to fix certain issues. Another thing you may wish to try is updating your roaming capabilities by dialing *228, choosing option 2, and then restart your phone. Call waiting is a feature that is available specifically while on our network. I hope to hear back with results so we can go further if necessary.
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