You didn’t actually say what’s the wrong information. It may not be as serious as you think
I’m stating the obvious here, but shouldn’t your consultant tell you what to do in this case? After all, you hired him/her to manage all aspects of your application. If you fired the consultant, then your best bet is to submit a formal letter via the web inquiry form as well as call up the CIC helpline and talk with someone to find out what you can do.
I imagine if your file is opened and they deem it as misrepresentation, they can bar you from applying again for a number of years?