The issue is that you had the website added to the staging website before. Then you copied the website to the live version and there you selected the MOVE option when a prompt asked that there is a new domain used.
That prompts WPML that the staging website is no longer in use.
But you seems to be needing to use the staging website, that is why the only option for you is to click the link mentioned in the screenshot you shared and indicate that the staging website is still there to use.
That will do the trick.
But if you want to have the option to set back and this time select the correct option of COPY you need to reduce the version of WPML by downgrading it so instead of the screenshot message you will have an option to select COPY.
Please consider that in the new version the prompt you see is by design to avoid confusion between the copying and moving of a website.
By the way, I wonder why you selected the MOVE option in the first place? There it was indicated that moving means that you do not use the staging anymore, was the messaging misleading or something else so we can identify if there is an improvement is needed for the prompts.
I know adjusted the setting, so it seems, two websites cant be worked on simultaneously. I can only have WPML working correctly on either the production or the development site
