Hello there. I'm here to assist you and provide possible reasons why the option to add deductions is not available on your end.

All payroll subscription levels provide the ability to add new payroll deductions. Regardless of your chosen subscription level, you can customize and include additional deductions or contributions as per your requirements.

On the other hand, you need the access or permissions in your payroll system, which could be why you are unable to add new deductions. 

See this article to learn how to add and manage custom roles in QuickBooks Online Advanced.

However, if you are the admin or have administrative privileges, there are troubleshooting steps you can take to resolve this issue. Begin by accessing QBO through incognito mode or a private window. This allows you to browse the web without saving your browsing history. To bring one up, follow these steps:

• Google Chrome and Microsoft Edge: Ctrl + Shift + N
• Safari 11 or newer: ⌘ + Shift + N
• Mozilla Firefox: Ctrl + Shift + P

If this works, return to your regular browser and clear the cache to start fresh. This troubleshooting will remove the outdated files that cause unexpected behavior in the online program. Alternatively, utilize another browser to see if the source of the issue is caused by the one you previously used.

But if you're trying to add a payroll type that is particularly a contribution not provided currently its not available. If you mean something else you can let us know. 
 

You can utilize this article to learn how to run, print, and customize payroll reports in QuickBooks Online Payroll: Run payroll reports in QuickBooks Online Payroll.

If you need to complete other payroll tasks, I'm here to lend another helping hand again.