Hi there, @Henry17.

Welcome to the Community. I can provide some clarification about creating invoices in QuickBooks Online.

The template names showing from the Customise option will depend on the information entered in the Custom form styles section. You can update the details in the system to ensure it will show what you need for your customers.

Here's how:

1. Click the Gear icon in the upper-right corner.
2. Select Custom form styles.
3. Search for the invoice template you want to use.
4. Press Edit below the Action column.
5. From the Design tab, edit the template name (ex. Banking details template). 
6. Go to the Content tab. 
7. Add a note.
8. Enter the necessary information.
9. Hit Done. 

Once done, you can proceed with creating the invoice. Please make sure to select the correct template for the banking details to reflect on your end (see screenshot below).

Also, you can view the full details by clicking the Print or Preview option at the bottom.

For additional reference, I've attached a link you can use about uploading a custom template in QuickBooks: Import custom form styles for invoices or estimates.

Drop me a comment below if you have any other questions. I'll be happy to help you some more.