It's nice to have you here on the Community page, @alexingamells.
Let me have the pleasure to help share information about running payroll in QuickBooks Online (QBO).
First, may I know what error/issues you've encountered when trying to run payroll in QBO? I've checked and verified that we've received several issues reported by other users affected about not being able to run payroll in QBO. A ticket was already submitted about the issue and our products engineers are now working for an immediate resolution.
To check and verify this further, I recommend getting in touch with our QuickBooks Support Team. Once verified that you're one of the affected users, they'll be able to add you to the list of affected users and receive an email notification with the latest updates.