Final pay is usually delayed a few weeks because the Army will make sure you don’t owe them any money prior to cutting your last pay (such as for lost equipment, over payment during your service, etc). They will do an audit of your pay over your service time to make sure everything is balanced out. So, if you didn’t get it this week, it’s probably still being looked at. If you don’t have it in a few weeks, call your previous post finance office.