Need help on Commissions sales and legal advice

Hi, I have been working at a job for about 2 and a half years. The past year, the company started to pay employees commission for sales of accessories at the end of every other month. I am in a position that does not work at the front desk, which excludes me from this commission payment. I am the only one in the company assigned a task not working up front to sell accessories. I want to know what kind of legal advice can you give in order to confront the manager to allow me to work up front in order to participate in commission sales. I have also made flyers for each worker to give out to help them make commission sales and have made a small ad that is used on the front desk to get customers to buy accessories. The manager has set rules that whoever convinces the buyer to purchase the accessory gets the credit for the sale (and must be included on the ticket) even if someone else rings up the customer. Also, any google review left for the store with a worker's name in the review gets commission pay from that as well. These ads and google review flyers that I have made have been used for a year. Should I request commission back pay for the use of my ads? Is there something called that? Also what else in the commission laws can I mention to my manager in order to get some kind of compensation for lost ability to participate in commission sales? If you need more info, please ask. Thanks.