Hi there, I worked in the cake shop for about 3 weeks and two days in June, then I quit the job. After a few week, I still haven't gotten my payment. Then I messaged and emailed the owner, and he said I didn't give notice one week before, then he decided to withhold me one week's payment.. then 14 of July I emailed him again and said I haven't received my group certificate and the payment. He said he already sent out the cashier cheque and the group certificate but I haven't received any cheque. Until now I still haven't gotten my payment. What should I do under employment law? thanks