Welcome to OpenStreetMap and thanks for spotting this/updating the map. It can take a while for these changes to propagate to routing software, sometimes of the order of weeks.

It might work a little better if you add the gate as a node (point) as close to where it is actually located, tagged with:
barrier=gate + access=private + locked=yes

Removing the highway=service tag unfortunately means that OSM now thinks it has a very long gate with a lot of access tags.

If you'd like any help with this, please let me know.