Unfair treatment

Treatment I received from FNB Branch corner Main and Republic rd Ferndale teller and the manager that was working on the 3th June 2019 @14:10 was unfair. I have a business account and personal account with them and I gave them plenty business for my business vehicle finance more than three cars I bought with them. I believe to be a customer to them I can get help and correct advice. One of my customers paid us with stained money which I believe from either atm banking booming or cash in-transit hijack unfortunately my drive accepted the money. And I went to them (fnb main rd) to say how can they help me with this money because I bank with them. I think that girl thought that because I am a black person she can just start telling me I have ****** the money, R300. I said but I have too much to loose to come to the bank to be arrested for R300. The only thing that she could tell me was we are taking this money you will not get it back. And I ask how is this helping me as it is a transaction in my business which I have to have a record, and is it gonna be a matter of just just giving the money to you without a record even for bookkeeping. She left me on the counter to her so called manager, when they call me the only thing they say was, we will call police for you and you will tell them where you got that money. Well I felt that even if they had a right to hold that money but this was not the way I was suppose to be treated. What is it that tells me they don't take that money for themselves because there is no document nor paper work except telling me they will call police.