Thanks for following this thread, @FrankBurns4077. The contractors have their QuickBooks accounts where they can update their email addresses.  

Since the contractors' emails aren't updated on your end, I'd suggest you contact our Customer Care team to help you check what's causing this to happen. 

For future reference, read through this article: How to change the user ID or email address for QuickBooks Workforce.

Get back to us if you have additional questions. We'll be here to guide you more.