I call Sprint CS today to ask them if I could add a third line to my family plan using a phone I already have. I was thinking that since I already have a phone, I could add the third line without a contract but I was informed that even though I'm not buying a new phone at a discounted price, any new line has to have a 24 month contract.
I had that same response when I wanted to activate a phone for my kid. Didn't want a contract untill kid proved they were responsible. I just called retentions and activated it through them and they worked it out, didn't have to sign a contract. Give that a shot.
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