USPS tracking number not working?

[stackables]

I bought a set online and the seller gave me a tracking number and for some reason I am getting this error: "Delivery status information is not available for your item via this web site. A return receipt after mailing may be available through your local Post Office". The seller says that the number she gave me is correct. Does anyone have any idea what this means?

[Ed Mack]

I bought a set online and the seller gave me a tracking number and for some reason I am getting this error:

"Delivery status information is not available for your item via this web site. A return receipt after mailing may be available through your local Post Office".

The seller says that the number she gave me is correct. Does anyone have any idea what this means?

Very common issue. The USPS is not as adept as UPS or Fed Ex with their tracking numbers. I'm sure it will arrive before it gets activated. I have seen similar messages 40-50 times and all the items arrive safely.

[stackables]

Thanks for the info.