I fixed the error 504, it was a misconfigured php setting.
I checked also the permissions and the space left on the VM is 30GB.
Now I tried to deactivate the Amelia plugin and the deactivation is done.
Please continue to investigate on my website.
Thank you
I don’t know if it the right place to report a Amelia plugin error.
It does not work at all from the wp-admin and also from the home page.
When I land to amelia dashboard an error 500 occours. Another error 500 is thrown where I placed the shortcode in the home page.