error "You must enter a valid value for the Manager ID field. (PER-1530231)

When I transfer an employee and in the last screen (Assignment), I click "Submit" and it gives me the error "You must enter a valid value for the Manager ID field. (PER-1530231) Details: You need to enter a valid value in the field for the transaction to succeed. For example, you must only enter a number in the Job ID field."

Noting that i didn't change any of the employee's information whether in the Assignment or other fields.

And it happens with certain employees.

Position is overridden.

Regards,

Sara