I need an urgent resolution

I have been a long standing customer of Vodacom for many years. I have paid my account on time. I have recently been having very bad service especially when it comes to my monthly payments. I changed over from FNB to Capitec 3 months ago. I have a debit order mandate on my Capitec account yet for the last 3 months you have kept debiting my FNB account which has NO money in it. I keep incurring additional costs and keep having to make manual payments. I made a manual payment of R4357.66 on the 27th of May. Today i find that all my lines have a soft block on them. I called in at 08h35 today from my number *** (Not a contract number) and spoke to a gentleman by the name of Brandon (I might be wrong). He CONFIRMED that my account is active and NOT in arrears. I then get transferred to Shibu Makoela at 08h53 who tells me there was an additional amount of R4125.11 that was meant to be paid on the 1st of June????? Where did this amount now come from? Shibu says i need to pay R1500 to have the phones unblocked yet I have 2 small kids sitting at school who need me to contact them in order to arrange an uber to take them home. Apart from me NOT understanding where this additional amount has now come from i don't have R1500 to unblock anything. I need someone to contact me urgently regarding this as it is unacceptable that month in and month out i am having to experience these issues and all because i changed banking details.