Need Help Invading in BTS

[Kurgan1536]

I have been playing a game in BTS and can't figure out why I can't invade my last neighbour on the continent. I've made vassals out of 3 of my neighbours, but can't declare war on the last. It says I have a peace treaty with them, but I never signed one; we've never been at war and I thought that all I had was open borders. I'm currently downloading the patch, just in case, but I was wondering if their was a diplomatic restriction that someone here might know about. I've attached the file for review.

Thanks.

[Boracks]

If you made a recent trade with them, that would explain it. Some deals come with a 10 turn automatic treaty.

Helpful sometimes in securing a flank while busy elsewhere.

[Ming]

If you have "demanded" anything of them... money, techs, goods... that is the equal to a ten turn cease fire agreement.

[eris]

You have some trade you have made involving 6 gold per turn and gold for incense. Also, you just gave them a city, Gordium. The deals say 10 turns to go, so I guess you just did this all. Wait the ten turns and then invade. Or next time, invade first and deal later!

[Blaupanzer]

You gave a city to someone you want to invade on the very next turn? One of the techniques the game encourages is planning. Giving up a city runs up big positive points with the receiver. Further, you will have to take it back, ravaging some buildings without question. Thimk!