Question about Stock in Hand Quantity

First of all, My English is not good. I am from Pakistan and I am using Manager Desktop version. I have been entering my business data since January 2018. I found a bug in Stock in Hand Report. When I open Sales Invoice in edit mode then I see the quantity for a specific item Say 10 but when I see it in transactions, it shows as 2. So my stock in hand is wrong in this way. It should be Zero according to logic but it is showing 8 in remaining stock. I am attaching images. Please help me out.

Everything looks normal in the screen shots you posted. You raised sales invoice #33 for 10 units of Stapler Pin 24/6 on July 11. But you only had 8 units on hand. Since you are not using either goods receipts or delivery notes, Manager cannot sell inventory you do not have, because purchases and sales are considered to be complete the moment they are entered.

On July 15, you purchased 10 more units. Manager immediately dedicated 2 of them to the unfulfilled sales invoice #33.

Incidentally, I can tell by your screen shots that your software is quite a bit out of date. You should update.