User is able to Submit NOR with blank S2O Order number for the Missing Prefix SKUs

Steps to reproduce:

1. Login to the S2O portal with valid credentials.
2. Select the SKU with missing prefix as True.
3. Click on the SKU from the PIR grid.
4. Click on Submit NOR button and observe the results.

Expected result:

User should not be able to create any NOR for the SKU.

Actual result:

User is able to create a NOR for the SKU and the Order is displayed as blank.

Note: After creating one blank order and user is unable to create any more orders.