Well, according to your explanation I got an issue that I faced with the same problem before. We should avoid cancelling any order after taking the project from any client. So, what I know and expert I should take that project but what I don't know and not expert, we should not take that kind of project. Even, before taking any project we should discuss with the client clearly to know about the project requirements. If we don't follow this, then our reputation and the cancellation will increase, as a result our gigs and profile will go down. In my point, it's the main reason behind of it.