Thanks for visiting the Community forum. I'll share some insights about the delivery note feature in QuickBooks Online (QBO).
QuickBooks Online mobile app doesn't have the full functionality of the website version. Some features are limited on the mobile platform. With that, creating a delivery note is not possible in the app. You'll want to log in to your account using a browser, then create a delivery note so you can finish your task on time.
Moreover, I've included this article to learn which QBO mobile app features are supported on mobile devices: Compare mobile app features.
Let me know, and don't hesitate to click the Reply button below if there's anything else you need help with the delivery note option. I'm always here to help you anytime. Take care and keep safe!