Hi there. I'm here to help you get past this, so your account number will appear on your Chart of accounts (COA).

In QuickBooks Online (QBO), we can turn the account numbers on and off. To make sure that this option is enabled, kindly follow the steps below:

1. Log in to your QBO account.
2. Go to the Gear ⚙ icon and select Accounts and settings.
3. Click the Advanced tab and tap the Pencil icon on the Chart of accounts section.
   
   

    

4. Tick Enable account numbers and put a checkmark on ☐ Show account numbers.
5. Once done, hit Save. Then, Done.
   
   

However, if the issue persists, you may access your QBO using a private browser. It could help verify any excessive data issues with your regular browser causing this matter to arise.

Here are the keyboard shortcut keys to open a private session for each browser type:

• Safari: Command + Option + P
• Google Chrome: Ctrl + Shift + N
• Firefox or Internet Explorer: Ctrl + Shift + P

When you can generate your account number using a private browser, it confirms an existing data issue. Let's fix it by clearing your browser's cache and cookies. 

Nevertheless, if you get the same result after following all the steps, I recommend using another supported browser. You may also consider contacting our Customer Care Team to help you dig deeper into this matter and lay in a prompt resolution.

Finally, I'm adding this article that contains information regarding default accounts in COA: Manage default and special accounts in your Chart of accounts. It can also help you modify or merge accounts that can be edited and fused.

Let me know if you have additional concerns about the account numbers in COA by replying to this thread. I'm always available to assist you.