你的老板不能扣你工資

你的老板不能在你的工資扣除50元. As per BC Labour Standard, 

Text of Legislation

21. (1) Except as permitted or required by this Act or any other enactment of British Columbia or Canada, an employer must not, directly or indirectly, withhold, deduct or require payment of all or part of an employee's wages for any purpose.

(https://www2.gov.bc.ca/gov/content/employment-business/employment-standards-advice/employment-standards/forms-resources/igm/esa-part-3-section-21#:~:text=(1)%20Except%20as%20permitted%20or,employee's%20wages%20for%20any%20purpose.)

他要是扣你五十元, 你就打電話到Service BC, 再要求轉到BC Employment Standard投訴

說真一句， 找另一份工作吧。