In both the UAT and Live environment, sample API calls can be accessed from the Supportī Rest Testing Tool menu. 
Click on the dropdown for the service category and version you wish to test. In the below example, 'ProductsV4' has been selected.
Select the service you wish to test. Example below is Load Product Master Updates.
On the right (highlighted in red), you will see the list of all the fields. The format shown is determined from the "Parameter content type" dropdown (highlighted in orange).
To copy the example message highlighted in red, click anywhere in the section (highlighted in red). This will copy it into the "Request" box (highlighted in orange), where is it editable.
You can also set the content type you wish the response message to be in.
To submit the message on UAT, which will subsequently appear as activity on the 'Activity Monitor', enter a test message in the "Request" box and then click "Try it out!".
The Request URL, Response Body, Response Code and Response Headers will show below. This activity will also show on the activity monitor. 
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