I can’t “edit sequence” in Adobe Audition

Hello all,

I hope you're well. I'm hoping someone can help me as I've found no luck online. I need to move my premiere pro sequence to audition for the audio mix. Sounds simple right? I know! It should be. Normally I would select the video and audio - then edit - then edit in audition - sequence 

yet when I go to do it, sequence is greyed out so I can only do clip which isn't what I want as I need to edit the mix to the video. 

I'm new at premiere and audition so I'm sure I've done somthing wrong but I can't see what...