FNB has disappointed me

My business account has been placed on hold and I didn't receive any notification, I went to FNB branch in soshanguve crossing so I can understand what is happening. I was told that someone send R1400 from standard and then standard reported *****, ok I know the person who send me that money I asked her to make an affidavit and give it to me along with her bank statement and her ID copy. I emailed them to the person who is investigating my cas. That person never responded never called so I went back again to the branch, they just told me that they send an escalating email to the person. My friend went to FNB to ask why her account is not working, they told her that my account blocked her account. I'm not happy because I don't understand what is happening and this Beverley Nukeri that is handling my case is not saying anything. I'm running a business my customers are angry