Paid and have proof

<p>I have 2 accounts with cell c so I went to their customer care at their head office to pay, because I had problems with my banking details . I paid the whole outstanding amount for my two lines now they suspended 1 of my lines, saying I didn't pay I paid the agent put all the money on 1 line and not the other but I only get 1 statement not so how is it possible to overpay one and not pay the other. </p>