There is no message or notification in activity log to tell us that Salary slips already created by Process Payroll (when press create salary slip button ), I think V7 was contain this message.
Are you looking for the notification message in the Process Payroll or Activity Log? If you believe it’s an issues, please create Github Issue for it.
Issue is replicating in the test account as well. Github issue created for the same.
@ArundhatiS Ok thanks