I am really sorry for that. Here I would like to share something.
I know how are you feeling at this moment. This happened with me also. After submitting my documents, I got AOR but after that I got a letter from CHC, ND that my application was rejected on some wrong basis. I applied under NOC 4131 and they stated that "The institution where I was teaching was not a post secondary institute" but, In reality, it was only a Post Secondary Institute. Then, I sent representation to the Visa Officer in CHC, ND. But, they did not reply me for more than one month. After that, I sent them mail and fax as well and then they replied me after 20 days. They also called me and told me that they sent me a mail and they are willing to reopen my case. However, by that time they had initiated my refund, so they asked me to send them fresh fee once again. They re-opened my case and I sent them fee again. It was an incident that the day when they called me was the day when I got refund.
So, you never know what can happen with you as well. So, don't worry and send them representation.