Hi @CampaignerForLife ,
Go to /Administration/Configuration/Input forms/ and open Name: nms:delivery
Search for the keyword @deliveryCode
you will find the below,
<input xpath="@deliveryCode"/>
</container>
<input colspan="2" xpath="@nature"/>
After this <input colspan="2" xpath="@nature"/>,
add the below line
<input colspan="2" xpath="@yourAttribute"/>
and in starting of the input form, in the form tag <form .... you can able to see xpathsToLoad.
Here add your attribute. example, <form ............. xpathsToLoad='@yourAttribute,........'
Now when you create a new delivery, you can see the new text field under delivery > property > general tab