Hello there, info-! I'm here to help you to change your employee's status.
This error usually happens when entered numerical values for month, date, and year are interchanged accidentally. I recommend reviewing them following this format: mm/dd/yyyy. Please also ensure that the numerical values for hire and termination dates are not interchanged.
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I'm adding this article about your employees' pay history to ensure you get all historical paychecks: Add pay history to QuickBooks Online Payroll.
Feel free to drop by again if you have further questions about changing an employee's status in QuickBooks Online. Take care.