USPS Tracking API v3

Hello Postmasters;

I am having a dickens of a time trying to figure out USPS’ Tracking API:

I am able to get an OAuth just fine but for some reason I can not convey the token to the tracking call. I tried about every combination I can think of (Bearer, OAuth etc) and no matter what I do get tis error:
“apiVersion”: “/tracking/v3”,
“error”: {
“code”: “401”,
“message”: “The access token provided with the request is missing, invalid or has expired.”,

I forked Lob’s collection and still - no love:

Any help is appreciated!

Hi @flight-cosmologist-3

On the first link. Have you downloaded the Open API spec? …

This can be imported straight into Postman and it will set up the call as it needs to be, then all you’d need to do is add in the missing bits (auth tokens etc.).


Hi & thank you. This is a great tip & I suspect points to the root of my quandary.

The only changes I made were:
Auth Tab

When I request token in the Auth tab I get this error:
Error: Could not complete OAuth 2.0 token request

The attached image is the Auth Tab - I’m not sure if the ‘available tokens’ is correct - seeing the collection hasn’t received a token yet…


If you scroll down, have you clicked the get new access token button?

Yes, when I do I get this error:

The 401 is when I send the request.

I’m sure it’s something simple but running out of hair to pull out! :slight_smile:

Thanks again…

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.