People Search bars not working for some users

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Hello experts,

all line managers with the exception of one user can find people in search bars of their hierarchies but one of them cannot find anyone even if they have same roles and person security profiles set to View Manager Hierarchy.

What could it depend on? How can we solve this issue on single manager? Is there a batch process to be launched?

Thanks in advance for your time!

Kind Regards,

Valerio

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