[How do i make this quest non Repeatable.]

I have a quick question, How do i make this quest Non Repeatable. As in you can only do this 1 time, and if you try to do it again the NPC will say something like " Sorry you have already done this quest "

 

 

 

 

//----------The Log Quest------//

nov_gar01,98,84,0	script	Worried Girl	882,{

mes "Hey! Hey you right there. Do you think maybe you could do something for me?";
menu "Sure Maybe",-;
next;
mes "It's starting to get dark and I am supposed to be meeting a friend here, I'm worried she wont find me at this rate.";
next;
mes "Would you be nice enough to go find me some fire wood? If I have a fire there's no way she could miss me. I am pretty sure there has to be some around here somewhere.";
menu "I guess so..",-;
next;
mes "Thanks! Lets say around 10 pieces of wood.";
menu "I have the wood.",-;
if(countitem(6008) < 10) goto Lne;
next;
mes "Thank you so much! hopefully my friend shows up soon shes taking forever!";
delitem 6008,10;
close;

Lne:
mes "I don't think you have quite enough wood... Come back when you have more.";
close;

}