Hi ! Let's try to check what's happening here. Is your production stopped ? Do you have money to pay for factory wages ? What happened when trading Helium manually ? What happened with the trade route - did you "unload", rather than "sell" ?

I built this complex in First Light, it has 1 silica mine, 1 iron mine, 1 electronic foundry, 1 steel factory, 1 tool factory, 1 plastic factory, then 1 fusion power plant. I was going to build additional factories until I noticed fuel isn't producing and all resources slots shown sufficency, including credits but it didn't show helium3 slot being emptied. When I noticed details of complex, it mentioned helium3 is needed to produce fuel, so I created trade route for helium3 as I did with methane and dihydrogren to unload there from Spire sector. But the complex wouldn't accept helium3 as resources. As I said I tried manually transfer helium3 myself.

Today, I tried again manually transfer helium3, finally the complex accepted it, now fuel is producing. Must be bug like when I tried to travel to Tranquility sector but only took me to contracts menu. I found a solution to that is to exit then restart the game. But it didn't worked for helium3 unload until today after I started my pc. Maybe reboot pc is another solution I guess.