As an HR expert, it is important to address this situation with the utmost professionalism and discretion. It is possible that the new supervisor may be experiencing challenges adapting to their role, or there may be other factors at play. However, if their behavior is impacting the team's productivity and morale, it should be addressed.First, I would recommend having a private meeting with the supervisor to discuss their responsibilities and expectations. It is important to approach this conversation with a solution-focused mindset and offer support as needed. If the supervisor is struggling, offering additional training or resources may be beneficial.If the situation persists, it may be necessary to involve senior management or HR to further investigate the issue. It is important to approach any allegations of favoritism or misconduct with a fair and impartial approach. Resigning should be considered as a last resort, as it may negatively impact one's career and financial stability.Overall, addressing this issue will require patience, professionalism, and a commitment to finding a solution that benefits both the team and the company.