Cities not in trade network?

[gusty root]

After the 1.2.0 patch, many of my settlements are "not within trade network" of my capital despite being connected by roads via merchant, or having fishing quays connecting to a shared sea. Even after upgrading to cities, I'm unable to assign resources to the city producing said resources, resulting in lost benefits. It seems like these resources are being permanently locked out for the remainder of the game.

[elder otter]

I'm assuming you're experiencing this in a game that was created pre-1.2.0 patch? if so it may be a weird case due to pre-&-post patch logic clashing or something like that? If you have merchant units, are you able to re-build some road connections?