I have just signed up to QuickBooks a few weeks ago and half of my invoices have suddenly changed name to "AL Dental" I only did one invoice to them?

You've come to the right place, @rustysplumbing-h! I'm here to help you determine why half of your invoices were mysteriously changed. 

I recommend checking your Audit log. This report helps you keep track of added, deleted, and modified transactions, as well as user entries. It allows you to see the history of changes made to these invoices. It can be customized by using the Filter tool to narrow down the data. 

Here's how:
 

1. Go to the Gear icon.
2. Choose Audit Log.
   
3. Use the fields on the Filter panel to select the user, date, and events.
   
4. Locate the deleted transaction.
   1. Use the browser search.
   2. Press Ctrl + F on your keyboard.
   3. Enter a keyword about the edited invoice.
5. Under the History column, click View.
6. You can find all the information needed for the transaction in the table.

It can be also due to outdated or corrupt cache files in your web browser. Let's try accessing your account through an incognito window to rule out the possibility of a webpage issue. You may refer to these shortcut keys to open an incognito window in all supported browsers:

• Chrome: Ctrl+Shift+N
• Firefox: Ctrl+Shift+P
• Safari: Command+Shift+N

If the transactions look okay, you may have accumulated too much historical data in your browser. I recommend clearing the cache so you can access QuickBooks with a clean slate. Alternatively, you can use a different supported browser.

For more information about using the search tools in QuickBooks Online, you can check out these articles: 
 

• Use the audit log in QuickBooks Online
• Find, Review, and Edit Transactions in Account Registers
• How to Search for Transactions

Please fill me in on your result after following the steps above. I'll be happy to help until it's resolved! Thanks again for coming to the Community. Have a splendid week!