check the physical cost and financial cost will be differ due to this you are facing the problem example is mentioned below.
item received with 10 $ qty 100 so total physical value is 1000 $ now you have transfer this item qty 10 fom one warehouse to other warehouse with same cost of 10 $, now 2 items is sold at 10 $.
now while invoicing you came to know that there are price different in supplier invoice so you changes and post the invoice.
this affect the stock at current warehouse which was selected in purchase order but didt apply to the warehouse where you transfer 10 qty.
due to this you are getting the error, to rectify search all that item make credit note for all item with the actual transfer cost the make inventory adjustment in warehouse where u received ur item then transfer that much qty to the other warehouse from you are making sale order.
hope this will solve your problem.
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