stock goes into minus

[gns001]

Hi
Please help

i don't you what i am doing wrong.

I have the stock grv after the order.
i can see the stock after that  in back office and in pos
have run the updates

but if i sell the only 2 items on a specific line that item goes into -1

is there a setting that i need to adjust

[Admin]

Your question needs clarification.