Nedbank is pathetic

I deposited money in my account it reflected on my account then I transfered it to my other nedbank my account was ok for 2 days today woke up today to the worst surprise my account 3 in negative and that deposit no longer reflecting .Nondumiso Ndlovu team leader said she will escalate and I will be called at 7 no one called till I reached out.Siya Ndlela then assisted still telling me he is not sure If they can rectify that negative as it's not my fault how would I have moved funds if they ddnt reflect.I need that rectified I don't need any negative balance in my account as it shows I leave above my means and that can affect my bond or my interest in car purchase as I have an huge increase in salary.The team leaders are not at fault their tried their best.Can this be rectified or cancel all accounts then I bank with a better bank that have their clients at heart