Answer : Each planet you visit that has a Rhymer Industrial Complex – Harvesting Facility is connected to the local Galactic Storage Facility (GSF).
Therefore you must meet two criteria. Be docked at the planet the harvester is located at and have sufficient space in your GSF to receive the resources.
As you can see from the image above there is a hover on the icon in question that then relates where your harvesters are located. You need to be docked at the same location. The interface will display all harvesters you have deployed in their various states.
Once you meet the criteria you will be able to successfully collect the resources.
