How can new user access our account, not an old quickbooks account?

Hi scarver. I'm glad you came to the community, this is the right place if you're looking for answers. From the sounds of it, you invited a new user and when they attempt to login it brings them to a different QuickBooks Online account.

This is pretty common whenever people may have started another QuickBooks Online Company in the past or even whenever they are a user on another account. It's actually quite simple to fix you just need to know where to look, so here are some quick instructions to point you in the right direction:

1. Select the Gear Icon in the top right corner. 
2. Select Switch Company in the far-right column

After they select switch company, they'll be provided a list of the available QuickBooks Companies. If this isn't what you meant, just leave a reply below with some more details so I can get back to you. Enjoy the rest of your day.