Local email not DKIM signed but remote does

[ffuentese]

Following this tutorial https://docs.vultr.com/an-openbsd-e-mail-server-using-opensmtpd-dovecot-rspamd-and-rainloop I tried to get a local opensmtpd server working. The thing is, some of the mail is locally sent (i.e. people enter the server itself to send email via mail(1) or mutt. That local email when its sent remotely to other servers is not DKIM signed and I don't know why.

Using:

• OpenBSD 7.6
• rspamd-3.9.1p0
• opensmtpd-filter-rspamd-0.1.8p0

This is my smtpd.conf

filter "rspamd" proc-exec "/usr/local/libexec/smtpd/filter-rspamd" 
listen on lo0 filter "rspamd" 
# listen on egress filter "rspamd" 
# listen on egress tls pki texto-plano.xyz filter "rspamd"
listen on egress smtps pki texto-plano.xyz filter "rspamd" 
listen on egress port submission tls-require pki texto-plano.xyz auth filter "rspamd"  
action "local" maildir alias <aliases>            
action "relay" relay  
match from any for domain "texto-plano.xyz" action "local"  
match for local action "local"                           
match for any action "relay"                
match auth from any for any action "relay"      

/etc/rspamd/local.d/dkim_signing.conf

sign_authenticated = true; 
sign_local = true;
sign_inbound = true;
allow_username_mismatch = true;
use_esld = true;
symbol = "DKIM_SIGNED";
try_fallback = true; 
use_domain = "header";
use_domain_sign_local = "header";
domain { 
	texto-plano.xyz {
	path = "/etc/mail/dkim/texto-plano.xyz.key";       
	selector = "default";     
		}
}