I added 1 employee to payroll last night, and clicked finish later. Now I am unable to add more employees
Thanks for sharing the details you want to achieve, @Dale8791.
Let's open your QuickBooks Online (QBO) account via a private or incognito window and add an employee from there. This is also to check if the issue is caused by stored data cache from the browser.
Pilled up data cache or browsing history causes unusual behavior to the browser that affects the performance of your QBO. To start with, you may use these keyboard shortcuts in opening a private/incognito window:
For Google Chrome, press Ctrl + Shift + N
For Mozilla Firefox, press Ctrl + Shift + P
For Safari, hold down Command + Option + P
If you're able to add an employee while in a private or incognito window, then we'll need to clear your regular browser's cache. This will also make your browser to function efficiently.
However, if the issue persists, I recommend using another browser. This way, we can check if this a browser-related issue.