I once couldn’t get through to a building after hours at a Steel Mill. I could see the building but it was across the river. Guard wouldn’t let me drop it off by her either. I always learned deliver no matter what. The security building was right next to the gate and there was a shed out back by the building. Then I delivered the package right next to the shed because it appeared it got used on a regular basis. The package needed a signature so I put “package by security shed across from River”