Shortcodes stopped working?

Dear team, first of all this is a great piece of code.However , suddenly
when I copy and paste shortcodes inside the main content editor, the shortcode is not “translated into” code.
It just shows [ninja_forms id=4] for example.

I have another 2 forms, however in these cases I use do_shortcode inside the template, and everything is working fine.

So is there any problem with that?