How do I Add branch to ABN. I am unable to connect to the ATO direct

Hello, Andrea64.

If you’re referring to adding another business to your ABN, you’ll need to contact ATO and apply to have extra business names added.

On the other hand, let’s try connecting to ATO again through a private browser. There are times that the overloaded files saved on your browser can cause unusual behaviors in the program. 
Here’s how to launch a private window:

a. For Chrome, press Ctrl + Shift + N.
b. For Internet Explorer or Firefox, press Ctrl + Shift + P.
c. For Safari, hold down Command + Shift + N. 

If it works fine, clear your browser’s cache and cookies or switch to a different one. Though, if the same issue continues, I’d recommend contacting the support team. They have more tools to help you investigate the root cause of this issue and help you fix it. Below are the steps to get in touch with them:

1. In your QuickBooks Online, click the Help menu in the upper-right corner.
2. On the Search tab, click an article and select Contact us at the bottom. Then, enter the details of your concern.
3. Choose how you would like to connect with them: either via Callback or Chat.

Please check this article for our support hours: Get help with QuickBooks products and services.

Let me know if there’s anything else about QuickBooks that we can help you with.