Usage of Key for site ( Live and Development site) Solution:
You will need one live key and a development key.
When you migrate your site from local to live or live to local the key will be overwritten with the one from the environment you are migrating from. There is no way to prevent this unfortunately
Go to your wpml.org account profile and remove the key generated for the site you are attempting to register (remove all 3 of them)
Then go to Plugins->Add new->Commercial tab
Unregister WPML or Register WPML and click on "Get a key for this site"
This will automatically generate a key code for your site Relevant Documentation:
