Hi Hussein
Can you be more clear on this Issue? Looking after your issue what i understood is while hiring through PA40 using actions you might be using postion field drop down menu.
kindly answer the below questions
- Have you checked the plan version? has it been set to current plan(your custom one too, if u have)
- have you tried to check the Org units in Simple maintainence or Expert mode or Org & Staffing.
Kindly come with screen shots & with more detailed information
Cheers 
Pradyp