A Confusion

Let´s face it, the vast majority of us need some money badly. I´m not an exception, and the other day I made the decision to go to the bank and ask for a loan. I knew that the answer was going to be negative, but I decided to give it a try anyway. I had nothing to lose.
The first surprise came when I entered the manager´s office. The manners of that man were exquisite, he kept telling me what a good client I was, how honoured the bank was for doing business with me and so on. I was stunned, so I thought to myself, this has to be a joke!. However, the manager went on and on, as if he were making a speech. When I was about to ask him for the loan, a bank clerk entered the office and called him out of the office. When the manager was came back, his expression was totally different. The man looked really embarrased." There has been a terrible confusion", he said to me. Then , he explained to me that he was expecting one of the best clients of the bank at the time I arrived. He had taken me for him, because our physical appearance is very similar. I asked for a loan anyway, but it wasn´t possible.
We will never know what would had happened, if the clerk hadn´t entered the office.

There are very few errors here. Well done. I removed the quotations marks on 'this has to be a joke' as you didn't say it, only thought it. Also the reported speech of "There has been a terrible confusion." doesn't seem natural. I know hat you mean but I think it might be better t say there has been a terrible mistake and I am sorry for the confusion....

It just goes to show the more money you have the more you can get. The less you have the more they do not want to know you.

Overall, this was very good.