Is my receiving a commission lawful for selling foreign currency to a company whose local currency income does not cover its expenses, knowing that I am selling it to them at the prevailing market rate?

If the questioner is an employee tasked with buying and selling currencies for the company, then his work and his wage are permissible and lawful as long as he adheres to the conditions mentioned in Fatwa No. 31842. Similarly, if he acts as a broker for the company in this work, it is permissible for him to receive a wage or commission for brokering this activity, as it is a legitimate endeavor.