BHOD - Nagios Plugin returns null

Hello, I’m lost and need some help, I stumbled upon the site, hope you can help

Running a check command for our my account app
define service{
use generic-service
host_name myaccount
service_description MyAccount Login Time - Medium Account
check_command check_myaccount! [email protected] password 10 13
}

define command{
command_name check_myaccount
command_line /usr/lib64/nagios/plugins/check_myaccount $ARG1$
}
[root@monitoring01 plugins]# su nagios
sh-3.2$ /usr/lib64/nagios/plugins/check_myaccount [email protected] password 15 20
TIME OK - 2.43 | time=2.43

but nagios returns
(null)

Please help