When testing an API from API Explorer it is noticed that an additional query parameter is being added to the URI
The timestamp being added is a common practice to avoid the caching issue when communicating to the server. This is done to provide a unique URL to the browser so it will fetch a new copy from the server rather than retrieve from cache. This should not cause issues with the API.
If for some reason this does cause a problem you can use a simple regular expression to remove the offending parameter. Ultimately though the API should be reviewed to determine why it cannot handle this value.