How to Set a specific GTranslate original language per post

Hello
I am using your amazing plugin
It works fine and thanks for this.

Listen, I set on the plugin the?original language of my website in Italian

Then, I have a post on where I need to set the english as original language because is written in english. Now, I read on Chat Gpt some indications to obtain what I need it in adding these two shortcodes at the start and the end of the post

[gtranslate lang=”en”]
content
[/gtranslate]

Unfortunately it doesn’t works and the opening shortcode is printed at the start of the page even if, I am using other shortcodes without any issues

Its possible to set a specific original language per post in a place of what I set for the entire website?

Thanks for you help
Your plugin is amazing!