invoice file name when downloading

Hello

I have created a custom template for my email, in a folder called yourtemplate in my child theme.

Now, when I generate a PDF invoice and download to save it, the default filename is “invoice” plus the number.

The word invoice is shown in lower case

Where / how can I set the default name for this to reflect my business name

I tried just renaming the invoice.php to a new name to reflect my business name (changed nothing else) and got a “page not found” error when trying to generate.

thanks

Alex