I would like to discuss a task similar to “The next step falls between responsibilities.”

A possible distinction: The decision is made, but nobody takes on the next part.

Possible first output: A practical handover arrangement with named responsibilities, required materials and acceptance conditions.

I would like to check whether this first step fits our task and discuss terms for further work.

Our situation: [add details]
What we want to change: [add details]
What we have tried: [add details]