If you're still in the product trial stages of your hair journey, you're probably piling up on a few products that you don't care for. If you bought a product that had rave reviews and it ended up doing nothing for your hair or worse damaging it, you can simply give it away, sell it or you can call the company and voice your disdain for the product. Politely. Most times the company is more than willing to give you your money back, offer you a coupon or credit for another purchase or replace a bad/ damaged product.
I've called Neutrogena when there moisturizer made me break out and received a check in the mail by the end of the week and I've also called the ORS manufacturers when their moisturizer had separated from the oil and received another product.
Tools you will need when you call: A pleasant tone (don't yell, they want to help you), the product (to read the ID number from) and in some rare cases a copy of the receipt.
Do not be afraid to voice your dissatisfaction with a product! It helps the company to have great customer service reviews. That's why the company's number is on the product and that's why the contact us option is there on their website.