Situation:
I conquered Carali several turns ago. There is an incoming trade route from Nicaea (No ressource, worth 68 as export there). Both have pottery as only ressource. Carali has a shipyard.

a) No income as import in Carali for that.
b) No outgoing route from Carali - not a single one

Further info:
I own the coastlines in the western med from Rusicade to Massilia - so lots of possible trade routes like in 6.0
No sieges/blockades.

Several other cities with no naval trade, too.

Gruß
Joachim