Hi, @accounting582. 

Thank you for reaching out to the Community. Let me share some information about sending invoices in QuickBooks Online (QBO).

There are a few reasons why the invoices you send manually are not formatted correctly in QuickBooks Online. I can give you some tips on how to rectify this.

First, make sure you are using the correct email template. When you go to send an invoice manually, make sure you are selecting the correct email template that corresponds to the custom form style you want to use. To do this, go to the "Sales" tab and click "All Sales." Then select the invoice you want to send and click the "Edit" button. In the "Customize" section at the bottom of the invoice, select the appropriate email template.

Here's a screenshot for visual reference:
 

Then, click the Print or Preview tab to view your email. This is to ensure that your form style is active and is selected correctly.

After verifying that the selected template is correct, you can Save and Send your invoice or Save and Close it if you want to send it later.

Once your customer pays their invoices, learn the steps on how to record them in QBO through this article: Record invoice payments in QuickBooks Online.

 Feel free to visit us again if you have further questions, @accounting582. We're always here to help you. Have a nice day!