1- initiate a quotation(Add quotation)
2- Add only one item to the quotation manually(Add product manually)
3- list quotations and try to make a purchase or sales from that quotation
4- the sales or purchase page will be stuck with no supplier field and no item retrieved or listed because it is trying to retrieve un-existing data from the data base
5- suggestion is to offer an option to add item to database when adding item manually after setting category/supplier