How can we show the user that something exists but is no longer required?

Background

We are working on a system that's primary function is for users to upload / store data. As part of this, we have a section where we generate suggested documents to upload based on what they entered previously. The user can then add documents to the suggestion and leave some text comments.

Question

The user is free to edit the original data whenever they like, because of this sometimes the document requirements can become redundant (i.e. no longer required). Currently we remove them from the screen if the user has not uploaded documents against that requirement. However, if they have done something with the requirement, we need to show in some way that this requirement is no longer required, but it still showing because the user has put documents there.

Are they any good examples or generally accepted ways of letting the user know that a data item is no longer required?

Edit

To clarify on the way it works. The user will first fill out their core details in a form. For example, Country of Residence = UK. In the next stage the system will ask for documents to support those answers. For example, a utility bill as proof of address.

The user is always free to go back and forth and update both their core details and the documents. The question focuses on the scenario where the user uploaded their proof of address, but then changes the country of residence (hypothetically lets say to "Unknown"). The system then realizes that the user no longer needs to provide the proof of address, but since they already have we can't just delete it.