Service Request API Key

Service Request API Key

Hello,
I am able to pull information from Incident requests using the API key string:
https://server/sdpapi/request/19515?&TECHNICIAN_KEY=**************************************
But if I try to do the same for a service request, I get:
<?xml version="1.0" encoding="UTF-8" ?>
<API version="1.0">
<response>
<operation name="GET">
<result>
<status>Failed</status>
<message>Error when performing required operation.</message>
</result>
</operation>
</response>
</API>

Ideas?

                New to ADSelfService Plus?