I am trying to look up an invoice number and a estimate number, I have both numbers, how come quickbooks can not find it , they are correct numbers .

Hi North bay 1,

It's great to have you in the Community! I know how handy it's to easily locate your transactions in the program using various identifiers such as invoice number. QuickBooks Online has a powerful numbering system that not only enables you to keep track of your transactions but also helps to have your books organized. I'll be happy to help you with this.

The search bar or magnifying glass in QuickBooks Online enables you to quickly access transactions in your books using various information such as date, amount, description content, invoice number, etc. If you haven't already, I'd suggest heading there to locate your estimate and invoice. Because not every section in your sales form can be used to search for a particular transaction, it's important to ensure you have your invoice number in the invoice number field. The same thing goes for estimates. By default, the numbering field is turned off in the system. To turn it on, you have to follow these steps. 

1. Go to the Gear icon on the Toolbar, then Account and Settings (or Company Settings).
2. Select Sales, then click anywhere within the Sales form content section.
3. Turn on Custom transaction numbers.
4. Select Save and then Done.
5. Open an invoice or any sales form, and in the Invoice no. field, enter the custom number or letter sequence you want to use for your forms. The sequence you set here applies to all sales forms.

In case you're already using the numbering system of the program and unable to identify your transactions, I'd suggest following some troubleshooting steps to ensure this isn't a browser-related issue. Here are my suggestions.

• Clear your browser cache if you're using a browser
• Clear the app cache if you're using the QuickBooks Online app for Windows or Mac
• Try a browser if you're using the app
• Try a private browser window
• Try another browser type
• Make sure you're using a supported browser and system
• Reset your Internet or try on another computer or device

If you're still unable to locate your estimate and invoice after this, then checking your Audit log would be the way to go. The Audit log in QuickBooks Online is a powerful tool that enables you to monitor what's going on in your account. It's a great way to keep track of your steps and know who did what in your books. I strongly encourage you to have a look over there to see if there's any record related to your missing information. Simply go to the Gear icon then Audit log to access this feature. Here's an article for more details on that: Use the audit log in QuickBooks Online 

In case your data was deleted, you can recover it using the steps in this article: Use the audit log to re-enter deleted transactions

I hope this helps! You're always welcome to stop by if you need anything else.