Item Number doesn't work

Good morning, i'm waiting for my order 20013146239, but the item number given doesn't work. Steepost says : "Thanks for using Speedpost Track and Trace! There are no updates on your item yet and the possible reasons are:
Have you entered the correct tracking number? Please check and re-enter the right tracking number
Could your item be still with the merchant or its overseas delivery partner? Once your item reaches Singapore, we will update the status and deliver it accordingly!
Would your item be sent via the registered article service? Click here to check" when i type the number… When will i receive my order ? Do i have to worry ?