Account Issues

It has been 2 and a half months since my account was put on hold. I received a call from a bank representative and ask me a few questions regarding some transactions on my business account, I answered and he was happy and hung up. 3 Days later my account was frozen. I then got an email from another bank representative stating their suspicious which none were true. Again inwas asked various questions and I answered. Then ibwas given a reference to use and I was told to send an email using the reference as a the subject of the email and I should state in writing the transactions on the account and so on. I did so and the bank representative in charged rep**** back and informed me of an investigation and I was okay with that because I know I have done nothing *******. A month went by and I followed up and same excuse was given. Another month went by and I followed up again, I called the representative and we had a decent conversation. I asked when will the hold be released and he couldn't answer. I told him if there was evidence then authorities would have came to my house already and arrested. I can't be stupid enough to partake in ******* matters using my real identity and address. He agreed and said he would contact the investigating officer and get back to me. This was last week Wednesday and still I have no response yet every month the bank has been deducting the monthly account fee which is bizarre because the account is on hold for me but not for the bank? So the bank can still take my money yet I can't use my account? That does not make sense. I work hard for my money and this has taken a huge toll on me personally and in a business sense. I cannot invoice clients using the business account due to it being frozen which then makes me look dodge when I am dealing with a corporate and I supply personal banking details yet the invoice has business info. I have lost 3 very big clients because of this whole bank situation and I am very unhappy. I need to know how can I get this matter resolved ASAP. Whether I need to go to head office or wherever the department that is in charge of such cases are so I can go because this is trash and I need my account active again.