Calling REST API in Postman

[Lori Milam]

I inherited a collection of API calls to create a project and all of its pieces according to our company's standards. I have created my token. I created username and password global variables and have populated them with the correct values. All of the API calls are then using the global variables for authentication. When I attempt to run the collection I receive 

"You are not authenticated. Authentication required to perform this operation." on the first API call. 

I don't understand what I'm doing wrong or missing. I've searched through the community looking for things that I might be missing and I don't see anything.

Does anyone have any ideas?

[Chris.Phillips]

It would help if you posted why kind of authentication you are using.

For reference:
API authentication and authorization in Postman | Postman Learning Center

[Lori Milam]

Sorry it's Basic Auth.