Legal Question in Employment Law in Louisiana

I'm not sure I understand what you are asking. When you say that you need a "termination letter," are you talking about a letter explaining why you no longer work there - sometimes referred to as a "pink slip"? If so, it is not customary for employers to give those out if the employees quits (as opposed to being fired). In any event, an employer is not required to give out a "pink slip" regardless, so unfortunately there is probably nothing you can do about it.