List workflow with “Start workflow when an item is changed” will run twice when creating a new wiki page

I have created the following workflow on the wiki page library to run when an item is changed:-

And it will send emails as follow:-

Currently when a user creates a new wiki page and he enters the wiki page name.

Then he enters the content and click on save.

Then two duplicate emails from the workflow will be sent ? So can anyone advice why creating a new wiki page will fire the workflow twice ?

Thanks