Convalid multible draft doesn't change stocks

Hi there,
I have validated something like 100+ drafts in my customer order list in a single time by selecting the check box but my stocks hasn’t been updated. If I reopen the document one by one and validate it again, the stocks are calculated correctly, am I doing something wrong?

Here is also my configuration of the module:

  • Decrease physical/actual inventory at sales order validation: True
  • Increase real stocks on manual dispatching into warehouse, after purchase order receipt of goods: True
  • Stocks can be negative: True

Other settings to false.

Can someone help me out?

Thanks in advance,
Giacomo.