If it is change of mind, you may just refuse to sign and receive the parcel when it arrives. You tell the shipping partner off that you do not want the product anymore, they will return it back to the seller. They might call you and ask you whether you want to take the product from their office or not. What I did was I just left the item aside and get my refund back after returning back the item to the seller. This overall process might take up to 1 to 2 weeks. If it is possible to cancel your order before delivery, it would be best and you can get your refund within few days.

Full refund. No penalty or process fee. Yup, the package has to be in sealed condition if the reason for return is change of mind. But for my case, nobody was at home to receive the parcel so I didn't give shit about it. For your case, you need to do fill up some online return form from Lazada website. You may refer to the return guidelines provided on the website.