The Scrum Master should talk to the IT manager and explain that progress in Scrum comes from inspecting an Increment at the Sprint Review. This is because:
* The Scrum Team is self-managing and does not need to report to anyone outside the team1.
* The Sprint Review is an event where the Scrum Team and the stakeholders collaborate on the product and inspect the Increment2.
* The Increment is a concrete and usable outcome of the Sprint that provides a measure of progress and value delivery3.
* The IT manager can attend the Sprint Review as a stakeholder and provide feedback on the product and the process4.
References:
* Scrum Guide, page 7, section "The Scrum Team"
* Scrum Guide, page 13, section "Sprint Review"
* Scrum Guide, page 10, section "Increment"
* Scrum Guide, page 14, section "Sprint Review"