Why can't I discuss "Don't convert my cities"?

Teddy from USA is trying to convert my cities. He has used missionaries to spread religion.

Why can't I see the Discuss option to ask him to stop?

Solution 1:

I haven't confirmed this, but I believe that you can only bring up this topic of discussion after one of your cities has been converted.

Note that using a missionary does not mean your city is converted. Conversion happens when the majority of citizens follow a religion. If a single missionary was used it may be that only some citizens became swayed, but not the majority.

I have found that the AI never brings this up with me until I fully convert at least 1 city.