Sale Order Issue

Dear ,

i use jde 9.1.5 i have the following scenario:

1.enter SO with qty 2.

2.print pick slip with qty 2.

3.confirm SO with qty 2 so F4111 and F41021 updated with qty.

4.modify the SO qty from 2 to 1.

5.Print invoice with qty 1.

6.run sales update with the new qty 1 with PO 3  tab update is set to blank to update F41021.

so what i have now after this scenario is i issued qty 2 and recorded this in F4111.but i invoice and update in qty 1 so we have difference between inventory and GL.

how to prevent this risky scenario?

Thanks,