Thanks for visiting us here today, @pmdonn.
I'll make sure you're able to override the pension percentage for your employee. Since the payroll information is in sync with QBO Advanced payroll, it is best to contact People's Pension Support. That way, they can walk you through adding the amount.
You can visit your pension's website to reach out.
Additionally, here's a link that covers all the tasks you can do when using advanced payroll: QuickBooks Online Advanced Payroll hub.
Please know that you're always welcome to swing by if you have follow-up questions or concerns with payroll. Just drop them in the reply section below and I'll be happy to answer them for you. Take care and have a good one.