Hi please can you let me know how to change the due date on my creditors and debtors invoices

Hello, daphne6. 

I can walk you through how to change the due date in your invoices. Here's how:  

1. Go to Sales.
2. Select Customers, click on the customer name. 
3. Under Transaction List, tap the invoice you want to make changes. 
4. Drop-down arrow under Receive payment and choose View/Edit. 
5. Change the Due date and press Save and close. 

Just in case, I'm linking an article about receipt term for future reference: Due date and invoice date do not match when using due on receipt term. 

You can always visit me here if there's anything else you need, I want to make sure you're all set. Have a great rest of your day.