A Payroll relationship gets created automatically when you hire an employee or create other types of person records, such as candidates and pending workers. A payroll relationship is an association between a person and a payroll statutory unit.
It is the same number as person number or assignment number(s) but few cases you would find where it doesn't matches or not in sync with person number.
How we can correct this?
There are two options:1> Prerequisite: "Person Number Generation Method" must be set to Manual
(Setup & Maintenance > "Manage Enterprise HCM Information")
> Now search the affected Employee from person management
> Go to Manage Person, scroll down and edit the 'Person Number' and save/submit.
> Re-search the employee and numbers should be in sync
2.) If there are more than one employees affected or above option doesn't work run the 'Payroll Relationship Number Upgrade' process
> First create a (Payroll > Object Groups) Payroll relationship Group with affected payroll relationship numbers
> Then Payroll > Submit a Flow -> 'Run feature upgrade ' and select 'Payroll Relationship Number Upgrade' process
>> Provide the above crated Payroll Relationship Group as free text in Additional Information field
It should solve the issue.