Wesbank and poor communication lines and emails

I have never seen such a big company with a bad communication services, when you call you stay hours on the phone before you reach them, when you finally reach them whatever you say falls to deaf ears, i called to asked them not to debit on my account since i was done paying prior to the account the lady pretended to hear me, they debited R8000 which i still dont know why, i later called back to ask for my money back after hours of waiting i was told to go to my bank to get proof of payment which i did, i have since emailed it to the email they provided it has been four days no response nothing.. what should one do????