Alliance bug? (Not a Bug)

[Sway1205]

I'm currently playing a single-player game with 8 civs in total. I'm playing with Rise and Fall rules as Russia with a primary focus on religion. I've been a declared friend of Kongo for nearly the entire game and have had an alliance from the second we were both able to. Now at turn 220/250 I no longer have the ability to form an alliance with him like I did before. I can form the specialized alliances like cultural, religious, etc, but there is no option to form a non-specialized alliance in the trade menu anymore. Note, this is not specific to just the Kongo. I can no longer form non-specialized alliances with anyone, but I noticed it with the Kongo because he was always renewing the friendship as soon as it was expired and then not soon after we would be in an alliance.

I'm not denounced by anyone and I've been friends with the three people I tried to make alliances with. I have no idea why the option to form a non-specialized alliance has suddenly disappeared when it has been present and used for so long in the game. Has this happened to anyone else?

Thanks.

 

[Takfloyd]

Non-specialized alliances haven't existed in the game since the first expansion, so you must have been imagining things or used a mod.