If you are channel manager or a financier on the platform, you may be in a position to approve or reject an operations task or milestone.

Note that you can currently approve or reject an operations task or milestone only if the associated milestone has been submitted for approval.

Once on the project, you can click the operations icon in the upper right navigation bar.

Once in the project view, you can either approve / reject a milestone or a task, as shown below.  You can also add comments to the milestone to provide the submitter more context around your decision.