Sidechain Option Missing

[Jason31695741hcg4]

When I select the scrolldown menu to select "add sidechain," the option is no longer there. It used to be there, but now you can only add a bus. Did I do something wrong? 

[SteveG_AudioMasters_]

Well not really wrong, but you've left out something important. You need to have a side-chainable effect in your session first before that option becomes available in the side-chain drop-down menu - simple as that.

[Jason31695741hcg4]

Ok, I do. All those effects are on the tracks and not clips. The sidechain button is missing on all of them. 

I have six other sessions mixing songs for the same band from the same show. All of the other six have the sidechain option and the one I'm having the issue with used to but now it's gone. 

[Jason31695741hcg4]

Also, the exact same effects on other sessions are able to sidechain as well.