Shocking service!!!!!!!!!!! Beyond wits end !!!!

I am so exceptionally at wits end with this company !! All i am trying to do is settle my account and the absolute lack of service is appalling ! My Brother made a payment to the account in April in error direct to Avis as opposed to Nimble. I did however send the POP to the consultant who was assisting me via email on the 18th of April and asked her to confirm all was in order. Her name is Fyroez Adams, She did not respond at all. While i fully accept the error with the April payment was on our side, a response of some sort would have been appreciated from Fyroez. Since then i have still continued to pay my account monthly but the R 400 from April has still not been allocated to my account!! I have been told they needed to contact Avis to pay the funds back to them. This was in in APRIL! I was first told it would take 3 days , then called again and was told it would take a month . then called again and was told it would take place on the 7th of the month . After numerous emails and calls and escalating, the issue is yet to be resolved. I have even asked if i can please contact Avis myself at this point ! Since the 18th of April Fyroez Adams has FLAT OUT ignored at least 6 -8 of my emails over the past month. She has not bothered to respond to the emails or even call me . I have escalated a while ago to her manager Andrew Peterson who has been CC'd in on every email and he himself has not even bothered to make an effort to respond or update me . I have also dealt with a Candice Edwards who low and behold also has FLAT OUT ignored every single email. I m beyond appalled at this level of service . We are now nearly in JULY and still no resolution in sight or even a simple update !! if there is any way i can escalate this to a manger who will actually take the time to respond it would be a miracle!! I honestly can say that I am beyond exasperated !!!