Are you flying a cargo ship ? Do you have available cargo slots ? Does the station have stock left ?

Well, this is an interesting story, a little mystery actually. Sit tight!

- I ordered some new cargo ships at Blue Hearth, but the production was halted due to lack of materials. This started basically on day one.
- I set a trading route to provide steel to the Shipyard, since clearly they need Steel, and I want to get my order manufactured. The route include Steel to the Shipyard and Plastics (if I remember right) to Miner's Hearth. [kudos for the names of each sector, they are easy to remember and make sense!]
- My trade fleet is generating income, therefore I assume the matter is being solved. Each sector has offer/ demand of the resources I want to trade for profit.
- After few cycles, I notice the Shipyard still misses the same digits of Steel (73 units). At this point I decide to take matters in my hands. I am on a Ghoul (little cargo + some defenses), so I fly to Miner's Hearth in way to purchase those 73 units of Steel and make a delivery myself. But here I find the situation explained in the thread.

TODAY:
- I noticed I made a mistake in the queue of actions in a sector, lol, asking my fleet to buy Steel before have sold Plastics. Fixed that, waited some weeks, but the Shipyard still misses the Steel, as if my fleet would sell it to some other station.

You mentioned Cargo Ship, does that imply I cannot buy any good while piloting a Ghoul? Ghoul has cargo space. Therefore, if for some reason an armed ship cannot trade, I beg you to change that ASAP.

Stations are waiting for resources. OMG I am so blind!!! :(
Luckily my fleet somehow manages to find steel to sell (probably that's why they need 3 days trading there every time)
I discovered how to command a fleet to sell exactly where I want. Call me impressed
How do I know what exactly they need? They use Fuel, H2 and FeO.

You indeed can't trade anything with a Ghoul or any other military ship. As to the need of stations, the resource cycle for the resource they are producing is outlined in the station menu, at the bottom end - every factory should have a little box with the current status, and which resources are needed for the output. Generally, all "Input" resources are required for the station to run.

If you want us to check on your save that everything is behaving as it should, be sure to open an issue at http://dev.helium-rain.com, and provide us with your game save as explained on that page. We'll load it here and go back to you.

Okay. Will take a look.
Please give armed ships some cargo to move goods.