I am using Core Payroll. The employer address has been updated on payroll setting plus the company setting. For some reason the old address is still showing on payslip.

Hello and welcome to the QuickBooks Community, bookkeeper1-live

We'll be happy to assist you with updating the business address on the pay slips in QuickBooks Online Core Payroll. 

First, please check that the correct address shows within the General tax info profile (Take me there).

Please then confirm if the payroll for the period that the pay slips are relating to was ran before or after updating the address in QuickBooks. We'll be on the lookout for your response!