Good day, does anyone know how to RETRIEVE customer statement sent 2 months ago with statement reference number?

Good day, Buck Tsai.

You can run a report to view all the customer statements you've created two months ago. From there, you can view the statements and print or resend it with the reference number.

I'll guide you through the steps below:

1. Go to the Sales menu and select the All sales tab.
2. Select the Filter drop-down menu.
3. Click the Type drop-down, select  Statements. Select the Date drop-down, and which option you'd like to use (in your case, set it to two months ago). Customize the Customer filter and click Apply.
   
4. You'll see a list of Statements, choose the statement you want to retrieve and click it to see the details.
   
5. Click the Print or Preview to view the Statement No. Then you can Print or Send them to your customers.
   

I'm adding this article for a more information about customer statements in QuickBooks Online: Create and view customer statements.

Please let me know if I can be of additional assistance or should you have any follow up questions. I’ll be here to help. Have a good one!