RestFul api issue on private instance

I have a private instance of WebPageTest set up for me and I am trying to invoke a test using WebPageTest Get call.
However every time when i hit the api, it triggers 2 tests (with same parameters) against one api call.
Does any one have any idea why this happens.

Api Call:
https://webpagetest.aws.hotwire.com/runtest.php?url=https://www.hotwire.com/&runs=1&video=1&timeline=1&private=0&k=XXXXXXXXXX&location=us-west-1-linux:Chrome.Cable&f=json