REST request connection to ALM 11

I'm running a REST request step to get a test instance using the resource path /qcbin/rest/domains/{domain}/projects/{project}/test-instances/{Test Instance ID} with the endpoint added also. I have a username and password entered in the Aut tab and have checked this username is authenticated for ALM. I run the request and get the following in the response:

<h1>HTTP Status 401 - Authentication failed. Browser based integrations - to login append '?login-form-required=y to the url you tried to access.</h1>

Any ideas? I already accessed http://yourALMServer/qcbin/rest/is-authenticated?login-form-required=y and checked my username and it's fine