You need to use transaction CO09 to view ATP quantities.MD04 gives an overview of the stock level and the requirements - but that not necessarily equals ATP.
You should raise a ticket with your company's IT department / contact your SAP Consultant . Nobody here knows the set up of your system or can investigate.
First you say: "My client wants to create a partial sales invoice (F2) from a sales order without delivery."Then you say: "I have changed the billing relevance of the item category to K."Please read the description of billing relevance 'K': "Delivery...
You don't need to include the packaging material already on the sales order. It can be determined automaticaly on the delivery. On the delivery type you can activate settings "Automatic packing" and "Gen. pack.matl item". Item category determination ...
Cancel the S1 with an S2 is only applicable in some excpetional cases - see: Solved: Cancellation of cancelled invoice (SAP note 388489... - SAP CommunityFurther, did you check with your Tax department if an S1 cancellation of a commercial invoice to...
