You have configured your domain with Nginx “Aplicación FPM servido por nginx” in Plesk, and WordPress redirects or friendly URLs are not working. This is normal: even if you have created an .htaccess, it will not work, as Nginx does not recognize .htaccess directives.
To use redirects and friendly URLs with Nginx in Plesk, you must open your subscription and go to “Sitios web y dominios > Configuración de Apache y nginx” and, at the very bottom, fill in the “Directivas adicionales de nginx” section with this content:
if (!-e $request_filename)
{
rewrite ^(.+)$ /index.php?q=$1 last;
}
# WordPress multisite subdirectory rules.
index index.php;
# This order might seem weird - this is attempted to match last if rules below fail.
# http://wiki.nginx.org/HttpCoreModule
try_files $uri $uri/ /index.php?$args;
# Add trailing slash to */wp-admin requests.
rewrite /wp-admin$ $scheme://$host$uri/ permanent;
# Directives to send expires headers and turn off 404 error logging.
location ~* ^.+\.(xml|ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|css|rss|atom|js|jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|ppt|tar|mid|midi|wav|bmp|rtf)$ {
access_log off; log_not_found off; expires max;
}