How to resolve "First View: Test Error: Error configuring traffic-shaping"

I have installed webpage docker on ubuntu operating system,
I have used the following :
As server : https://hub.docker.com/r/webpagetest/server/
As Agent : https://hub.docker.com/r/webpagetest/agent/

While running a test it is giving me error as “First View: Test Error: Error configuring traffic-shaping”

Any thoughts on it ^^.

For reference I have attached a screenshot.

if you are using MacOS you will need to disable traffic shaping. It doesn’t look like its supported yet.