I completely understand the inconvenience you have faced, and your concern is valid, @Nicola123. Let share some alternatives to help your customers to receive your emailed invoices.
First, you can ask your customer to check their junk or spam folder for the invoice. Then ensure that the email address associated with the customer's account is correct and up to date.
Given that the problem still exists after your troubleshooting efforts, I recommend contacting our QuickBooks Live Support Team. They have the appropriate tools to investigate your account, initiate a screen-sharing session to help you further, and may create a case for this issue if necessary.
To contact support:
- Select the Help (?) icon, then click Contact Us.
- Type in talk to a human. Hit Continue.
- Choose which way you want to connect with us: Have us call you or Chat with us.
I've also included the following article for your reference in managing your bank transactions in QuickBooks Self-Employed: Categorize transactions in QuickBooks Self-Employed.
If you have further questions about any QuickBooks-related concerns. The Community is available 24/7 for you.
