IDOC status = 51, article doc. created, why?

Hi,

User was posting WPUUMS.

The IDOC status was "51". A check with TCODE WPER on the same IDOC no. shows that the following error message.

"Deficit of SL Unrestricted-use 1 PC : 1122233001 1701 0001 (1122233001)"

Normally, when there is deficit stock, there would not have any posting on the article doc.

However, I got feedback and confirm that indeed, there had been an entry in the article document.

I don't think this is normal.

I suspect some setting error in configuration.

Can someone shared with me if you have encountered similiar problem?

Thanks in advance.

Bye