There are a few possible reasons:
The item hasn't been ordered yet. Your purchase order is still being processed.
The item is out of stock. Maybe your agent couldn't even place an order. Make sure it's actually ordered.
The item is still in the process of domestic shipping. China is a big country, they have different holidays and your items need to be handled too, so there are a few reasons why this could take longer than you think.
These reasons apply to all agents.
added: 8/17/2023 , modified: 8/17/2023