If I add new details/change original details to my customers file ie: phone number, this is not then showing up on the delivery note. Any advice??

Hi Jowettstone, thanks for posting on the Community

The customer phone number isn't designed to show on the delivery note - this will show the customer name and billing and shipping addresses. 

Please note changes will also only apply to newly created transactions (i.e. the delivery note will show the details of the invoice at the time that it was entered). 

If you have any further queries on this, please get back to us below.