Poor customer service

So I am a contract holder for MTN , now my issue is that I get paid on the 27th of each month , of which on their system they don't have the 27th as a debit order , so i get debited on the last day of the months 30th/31st earlier in November I made a query asking if uts possible for me to get debited right my pay they said no I then asked if i can pay using an EFT the answer was yes and then I figured out how , and got their banking details ,on novel paid using an EFT and my pay was allocated that's fine

Then December I did the same I paid using an EFT I send a proof of payment advising that I have paid already like I did in November and the agent gave me a feedback that my payment was reflecting in their system cool staff , to my surprise I got debited on the 31st, of which I made contact to state that I need them to refund me...it took a week for them to help until I decided to reverse the debit order because I urgently needed to use the money and the finance department was not even giving any feedback to even show they have received my query,I then reply to the communication advising that I have dispute my debut order they should now cancel the refund request. 2 days later I received an email that I gave skipped my payment my account is on areas , I called spoke to an agent and upon checking my EFT payment was showing , so she promised to escalate. Yesterday the 13th I received the refund , of the money I paid by eft , I had to pay again and now it's R30 short because of the bank charges this is an inconsistence to me because I am trying to do the right thing, paying immediately after my pay day, and now it's just a mess I will be on areas again and this is affecting my credit score I need you to train your agent to respond to matters and take customers seriously treat any matter as urgent to avoid such inconsistencies I am disappointed in you