QuickBooks Workforce is an easy-to-use online portal that allows your staff to access their pay stubs and tax information. It's important your staff is able to access it and use it without having issues.
I'd be happy to help get you and your staff back on track ASAP. Before we start, It's important to note that once your employee staff member accepts their invite, you can no longer remove their access to Workforce. Since you mentioned that your staff logged in successfully, I'm curious to know where they're seeing the message. If they're seeing this as soon as they log in, I recommend logging in using a private/incognito window. If this works, I suggest clearing cache and cookies on your browser as this fixes most issues the site is having. Here how: