Multiple metrics in the same graph

Hi, using raw edition version 2.3. I need to show 2 metrics of a service in the same graph. By default it is showing each metric in a graph separatelly.
The metrics are tx and Rx wireguard tunnel in mikrotik router using the SNMP nagios built-in plugin.
I tried writting a graph definition and put the script in ~/local/share/check_mk/web/plugins/metrics/ containing metric_info and graph_info, restart with omd apache restart but changes not taking effect.

The “service check command” is in service.
And booth the real names of the performance values are used in the script.
I got no errors, but no changes.

This is the code located in ~/local/share/check_mk/web/plugins/metrics/

from cmk.gui.i18n import _
from cmk.gui.plugins.metrics.utils import *

metric_info[“Iso.3.6.1.2.1.31.1.1.1.10.17”] = {
“title”: _(“Ifhcinoctets”),
“unit”: “bytes/s”,
“color”: “15/a”,
}

metric_info[“Iso.3.6.1.2.1.31.1.1.1.6.17”] = {
“title”: _(“Ifhcoutoctets”),
“unit”: “bytes/s”,
“color”: “24/a”,
}

graph_info[“demo_combined”] = {
“title”: _(“In out bytes per second”),
“metrics”: [
(“Iso.3.6.1.2.1.31.1.1.1.10.17”, “-area”),
(“Iso.3.6.1.2.1.31.1.1.1.6.17”, “area”),
],
}

Need some advice. Something is missing yet.
Thanks in advance.