The Product Owner is one person, not a committee. Sometimes this role is not considered seriously e.g. not having a full-time Product Owners per team. Few organizations fail to realize how challenging the role is and they overload the Product Owners with too many teams and backlogs.
Sometimes skills are not matching and training related to Product Ownership is not done. So PO fails to understand the fundamental of the role which in turn reflected in the performance of the team.
For the Product Owner to succeed, the entire organization must respect his or her decisions. The Product Owner’s decisions are visible in the content and ordering of the Product Backlog. No one can force the Development Team to work from a different set of requirements.
Apart from above challenges there are challenges related to missing product roadmap, missing/unclear acceptance criteria and changing priority during sprint.