Awaiting order, It has been 3 weeks. Could you help me.

Hi, I am awaiting my order from AliExpress which has been shipped through China Post Air Mail. The tracking number is RC719690275CN. When I check on your tracking service, the shipment is found but it does not tell me when I will receive it. Since it has been shipped on the 6th of March, I wanted to check how long it would take. Thank you