Dollar Tree review: The items were defective and the replacement as well

We bought supplies for our work from Greenbrier International Inc. We brought the order home and opened it, we found out that almost their item from the pack was defective. We took the order and returned it to the seller, who excused and promised to replace it. After 2 weeks we got the same order .No idea what to do, because we think that it was unavailing to replace it again.