A person or team working on a single problem at a time is typically more effective than one that is working on multiple problems congruently as they can fully focus and dedicate their energy to resolving the problem before moving to the next. Having a well-structured Product Backlog can help minimize dependencies and increase focus for each team.

The Scrum Master is responsible for promoting and supporting Scrum, which includes helping the Scrum Team and the organization understand and enact Scrum values, principles, and practices.
The Scrum Master should offer guidance that:
Addresses the root cause of the conflict, not just the symptoms or the consequences. Empowers the Scrum Team to self-organize and collaborate effectively, without relying on external intervention or authority.
Fosters a culture of transparency, inspection, and adaptation, where feedback is welcomed and used to improve the product and the process.
Focuses on delivering value to the customer and meeting the Sprint Goal, not on following a fixed plan or satisfying individual preferences.
Therefore, the best option is to address why requirements change during the Sprint Retrospective, which is an event that allows the Scrum Team to inspect how they worked together and create a plan for improvements. The Scrum Master should ask the Developers and the Product Owner to talk about why the requirements are changing and consider the impact on value during this discussion. This will help them understand each other's perspectives, clarify their expectations, and align their goals.

Explanation
Explanation:
The Scrum Framework only recognizes these three roles although others may be needed to help the team build the most valuable product possible.

The ones closest to the problem are the best ones to understand and solve the problems. The Scrum Master can remove members (if empowered). The Question : is focused on the ownership of the root problem. The Development Team is responsible for addressing internal conflicts and may request help from the Scrum Master if needed. Because this is a localized issue, they are the ones that must initiate the actions for the results they desire.