Not willing to do a cash refund

So I bought Micro Vacuum cleaner. The product does not pick up all the dirt from my carpet. So I returned the product and explained to a consultant that I'm not happy with the product and that its not doing the job its suppose to. They gave me an offer to take another product because its already over 14 days return policy that no one told me about before I bought the product or they can send it in for assessment.. So I told then that they should send it in for assessment then.. After 2 weeks, the product returned and they told me that there's nothing with the product.. And said that the product isn't made for carpets, and that its made for a person's car.. Last time I checked, the material inside the car is the same as my carpet. So the guy told me that there's nothing that he can do about it.. I just feel like I don't need the product when I can find another way to clean my carpet. I am not willing to take another product from Tevo, because first of all, the sales man didn't tell me anything about the 14 days return policy, and he didn't tell me that the motor of the vacuum cleaner isn't strong enough for any carpet kind of material. The product is still in good condition, and every thing is still inside. So I don't know what the problem is. They aren't willing to return the product unless I take something else and I don't want something else