Hi Pushkaraj
You need to change this configuration.. Refer note 19048, where SAP explains the same
Moreover, you can control at each asset level whether -ve values are allowed or not.. This config does not apply to all assets by default
Once you activate the -ve values allowed indicator in screen layout, you need to allow the -ve values in the Dep Area in AS02 as well... So, dont worry that the change in config will impact all assets
Br, Ajay M