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Ok after several attempts to try and get Nomorobo set up found out that the Simultaneous Ringing is not available yet! According to Cox Chat told me "Chris R.: Joanne, I have checked your account, in this case, I am sorry to tell you that simultaneous ring neither Nomorobo are available in your area, please check your bill statement every month in order to see when it is enabled. We are working as quick as we can in order to give all our customers this benefits in the closest future. However, there is not an estimated time". So now I left to wonder why it is listed in phone features but yet not available and they don't know when it will be?
Just because it's listed under Phone Features, doesn't mean it's active. Isn't it displaying Off, colored in a washed-out gray and non-responsive to clicks?