Nedbank South Africa Poor customer service

The worst service I received from Nedbank South Africa. I am a new customer with this bank. Sometime last week I decided to upgrade my car and sold it to a lady around our area. She is also a Nedbank customer and we decided together that she can transfer the money rather than cash withdrawals. She transferred the money to my Nedbank Account and within 15min I received an sms that the money was in my account. I gave her the car and papers,when I decided with my son to go out to buy some groceries we stoped at the garage to put fuel I then used my Nedbank card that was declined 3 times. I had to use my wife's bank card to pay for fuel. I went to South gate branch to quiery this issue. A lady helped me at enquiries firstly she said get a bank statement to Check if this transfer was lagitimet is the fund in my account. Yes the funds showed in my account. After a long que to the tellers I was told that my account was closed for investigation,how on earth is this happening to me. I was treated like a ******** for my own money. The lady that paid me came to the bank to testify and even gave a proof of payment still my account could not be opened. I stayed in that bank from 13.00 to 17.00 without help until I started making noise and demanded to see the manager. I was told to come back the following day yet I need my money now. I made some noise and the manager then unblocked my account. I am a customer why was I made to feel like a ******** like I had done something wrong by receiving my bulk amount into this bank. I will permanently close this account and use other banking institutions who cares for customers.