What if the courier didn't receive it three years ago?

I must have lost it. Generally, domestic express delivery takes more than one month, international express delivery takes more than two months, and international registered letters (that is, international letters) are not received for more than three months, which can be judged as lost, and the merchant will send you a text message to ask you to return a refund.

You can pay attention to the business messages three years ago, but three years is too difficult, so be prepared to be a big head.