Zapier multiple user

hello, I want to create a mission on my app for multiple user.

I don’t find how to do this. I can create a mission for a single user (I put the User Id raw) but impossible to dispatch it to multiple user (I try to put multiple user ID on the field but that doesn’t work.

I want to do this for that :
When I create a mission I dispatch it to an user.
The user can accept or decline.
If he decline, I want to share this mission to all the user.

Thanks for your response