Unsatisfied long standing customer

Iv been with rain for year. And Iv called to change my payment date to the 1st of every month and I was billed twice in Feb I made a payment on the 27th and I was billed again on the 1st which means I pay R499 for 4 days. Now my Wi-Fi is disconnected Iv been tryna get a hold of them and their network cuts and they don’t bother to call you back nonsense of a network my reference number ***2