HI Ab,
Pls. check your customer Master of Bill to party XD03,If you have maintained SH-Ship to party in partner function for your Bill to party& While raising Sales order if you have taken ship party then,It will be reflected on Invoice on Ship to Party at header level.
In your case as your ship to party is already marked for deletion -then how you-r - able to process Sales order.
pls. check your Sales order Bill to & Ship to party if it is same ...