When an estimate is converted to an invoice, it's taking the wrong invoice template.

Hello, @info-baainvestme.

When converting an estimate to an invoice, it will use the default invoice template set in your QuickBooks account. Let's review the default estimate template to match your invoice. 

Here's how:

1. Go to the Gear Icon.
2. Choose Custom Form Styles.
3. Click the New Style drop-down.
4. Select Estimate.
5. From the Design tab, click the Change up the template link.
6. Pick the template you want to use. 
7. Click Done. 

Just a heads-up, although you use Airy Classic as the active invoice template, the Airy New template will be used when converting an Estimate to an Invoice.

On the other hand, here's how you can mark a template as default:

1. Go to the Gear Icon.
2. Choose Custom Form Styles.
3. Look for the invoice and estimate template you want to use as default.
4. From the Actions column, click the drop-down arrow.
5. Select Make default.

You can read through this article for more detailed instructions: Customize invoices, estimates, and sales receipts in QuickBooks Online.

Lastly, you have the option to import your company's sales form template. For more information about the process, you can check this article: Import custom form styles for invoices or estimates.

You've got me here if you have any other questions with QuickBooks Online. I'd be pleased to help you out.