When you are setting up a new item sometimes you forget to flip parameters on and you might not noticed until a while after further setup. If you are setting up a produced item you should usually set the default order settings to a type of production order. The default is purchase order. If you don’t when you go to use the BOM designer it won’t show you the lines for the active BOM.
Here is a quick overview.
AX2012 R3 CU11
Cheers
Lachlan