Writing controller data to instrument track

I record midi on an instrument track. Next, I engage write and record my expression cc. When I do that, I end up with 2 controller expression tracks. They appear to be dublicates but one says Replace 1 part range. No idea what this is, or how to get rid of except to delete it. Any information why this happens?

why handle expression in automation and not in container?

I’m a new user. I don’t quite understand what you mean by “container”.