We want to make the delivery process as easy as possible and that's why we allow substitutions when items are out of stock.
When you're on a delivery and using the app, look on the page where you enter the prices and always read the section about substitutions.
The customer was asked which products are OK for substitution when they were placing the order. The app will tell you what they chose.
If they are OK with substitutions, there's no need to call them and you can simply change the product for a similar brand or size. Just write a note in the substitutions box on the app to let us know.
If you're not sure, or they didn't select substitution, you can still call the customer to check if they want one.