Any courier can look at the goods before signing. If he insists that you sign first without showing it to you, you can bring the bill and sign it. After seeing the goods, give him the bill. If there is any problem, cross out your name, or just don't return it to him. I buy a lot of things online every month, all of which are done in this way, so the courier company never dares to give me a hard time. Haha, I believe you have a way to deal with them now.