Identify the piece without losing the evidence
Ask the receiving contractor to retain the order reference, packing slip and a photo of the damaged area beside a wider view. Mark the corner on the approved drawing. A dent in a flat face and a twist at a folded edge may have different consequences even if they look similar in a close photograph.
Get one of three written dispositions
Ask the fabricator to say in writing whether the delivered condition meets the fabrication specification, whether it recommends a documented correction, or whether it proposes a replacement. The responsible buyer and installer can then record their disposition under the actual agreement. Ask how a correction affects the finish and any stated warranty. If a different profile or metal is offered to save time, compare it to the approved drawing before authorizing installation.
Keep the opening secure while you decide
Ask what temporary protection is necessary if the chase has already been opened and who will maintain it. Save the receiving images with the completion record. If a mark or leak appears later, the owner can distinguish the condition at delivery from changes after installation.