Here is your capital, circled in red.
By the current trade rules, you can only trade with factions where a trade route can be established from the capital.
Well, the only thing this settlement borders is a Norsan settlement to the north.
And they don't trade.
Which means you can't trade with anyone ever! (yes, I know if you conquer Norsca you will be able to trade - but you have a non-aggression pact with them from the start, and going to war with Norsca just because you need to establish a trade connection from your immovable capital is ridiculous in itself)
This mechanic desperately needs a fix, because despite Ghrond being your main settlement and having all the necessary connections there is still no trade possible. Oh, and abandoning/re-settling the settlement doesn't even work, is to forcefully moves your capital back, so the only solution is to completely abandon this settlement.
Please fix it, CA