I never bought from Lazada before, so I dun really noe how it works. Is the distro (or Lazada?) acting as the seller in this case? If distro is the seller, then if u receive a defective product (irregardless of deliveryman present or not), u can go back to seller to do 1-1 exchange. The deliveryman is only delivering the goods, he/she cannot act on behalf of Lazada/distro to do 1-1 exchange of goods. Of course, if u actually check before he/she leaves and u find defective goods, can tompang him/her to send back to distro mah

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But if u buy from retail shops, seller is the retailer not the distro. Need to find back seller, which is retail shop, to claim RMA. Of which retail shop may push blame back to distro. That's where the taiji starts, when retailer push to distro ("go distro exchange, I dont have stock here"), distro push to retailer ("go retail shop exchange, he agrees to sell to you, retail shop handles the defective product"). And u as consumer eventually get tired of this tug-of-war. Sad to say, unlike other PC parts that u can claim DOA (retail shop cannot test out part before selling mah, so push blame to distro), this casing thingy is considered physical defect, so unless got evidence, very hard to push back to distro. But u can still try and see whether distro allows or not.