The mailbox of US Immigration Service in China.

In your case, the package is usually lost. The American postal service is quite tragic. I lost my social security number and my work visa once.

If it takes more than three months, you can consider asking the immigration bureau to reissue a copy, which requires all the materials you applied for at that time. That is to say, you have to reapply, that is, the project is different and the speed is faster, but it takes about three months.