Introduce or enhance stakeholders management incl. engagement

In case of Agile, make sure to have PO’s high level engagement or someone with delegated power and authority. Or, align further plans and backlog priorities with PO to make data-driven decision during planning, and share planning results to other stakeholders to keep informed and aware.
Act as a mediator in communication between client and team, i.e. make sure to have team focused on sprint backlog while moving any informal request to Scrum master for further processing via formal flow.
In case of several decision makers / PO on the project, ensure proper alignment between them in terms of milestones, priorities, strategy, goals. If nothing present, introduce sync up calls prior to sprint planning to get to common vision. Another approach is to agree on power delegation to one representative who will act in alignment with other stakeholders with high interest and influence.
Communicate and work with stakeholders to meet their needs and expectations, address issues, and foster appropriate stakeholder engagement involvement.
Make sure to create and support stakeholder register with stakeholder classification, direction and influence, engagement model
Engage stakeholders at appropriate project stages to obtain, confirm, or maintain their continued commitment to the success of the project
Measure stakeholders' engagement and satisfaction, undertake corresponding steps based on the results

Useful materials