Self buying , fraud buying , multiple orders for same address from the brand itself

Hello, We are online seller . We are selling products at low rate . so brand itself buy many products from us . So in that case if they will return the product we have to bear logistic charges for the same ,So we have to bear loss without doing business And if they will accept the product then they may be damage the product and can return it after opening the package so we can't able to sell it again . So we have to bear loss without doing business and even we are not able to sell that units again as it's open boxed and it's electronic item . They did it indirectly . But we found that it was done by brand it self . But we found that person who order this is working in same brand (Using facebook and linkedin) . He placed multiple orders . There purpose is to damage us and they want to give us more products because we will think that we are getting more orders so we should buy more .And then we will stuck. They don't know that we knew this . It was happened just 2 days back , orders are still not delivered to them.Our employee wasted 2 days to identifying this person and trying to not to dispatch this orders after talking with marketplace but as per their policy they have to dispatch this orders and all the orders were prepaid and all the orders were dispatched . Who will use 12 units of same electronic device in a same home ? They wasted our time , money and want to damage us . We want to recover all the thing from them. So need help to take legal action against them .