Ok. Thank you!
Now everything is clear and solved.
Thank you for your quick feedback and for typo.
I have identified the issue. It was related to the security plugin All in one security settings. I have reseted everything and now is working fine with all posts.
Something extrange that I have identified is that WPP is working perfectly now with all posts and pages except with the main/index one. Is this normal?
I have checked the browser console in the main page and I dont see anything extrange (but Im not an expert).
Do you have any feedback about this issue with main/index page?
CDN is deactivated, just in case it helps you.
Thank you again.
PS: typo is now solved 🙂