Hello and welcome to the Community, Colibriteam.
I understand your concern regarding QuickBooks Online Payroll not deducting PAYE for an employee who exceeds the tax threshold. To address this issue, if this is the first time running payroll for this employee in QuickBooks, please check any year-to-date figures. It's important to ensure that the formations of your employees in payroll settings are configured correctly.
However, If it is not their first time on the payroll, please cross-reference the PAYE using HMRC's online calculator. If the figures don't match/no PAYE is deducted, I suggest contacting our customer support via chat to check the details in full.
I also suggest visiting this article to see the updates about Payroll Tax Year Changes 2024.
Let me know if you have any other questions. I'm a post away to help. Have a good day!