Azure DevOps API using PATs returns HTML in my PHP curl call, Postman returns Json

Trying to use the Azure APIs to build a web app that returns data from Azure Devops.

here is the API I'm calling: https://dev.azure.com/{{organization-pica}}/{{project}}/_apis/test/Plans/14/suites/15/testcases?api-version=5.0

POSTMAN: using basic authentication this works well and returns json result.

When I call this from PHP cURL it returns HTML?

Any help would be appreciated.