Is this really right if fiverr cancel the order after payment Clarence?

[shantosid]

I have worked for the client for 2/3 weeks. I have lost so many hours for him. After the work is done, after I get the money in my account(it usually take 15 days), the buyer send email to fiverr. They cancel order without asking me anything. Is this really a good process for a seller?? I am investing my important time to a project.