How do I make Stock -1 and account delete after randomly gened?

 if(message.content.startsWith(`${prefix}gen fortnite`)) {
message.channel.send('``Check your dms`` **You have been sent a  Fortnite account!**')
 if (talkedRecently.has(message.author.id)) {
    } else {
			var str = `Email:Password 1
Email:Password 2
Email:Password 3
Email:Password 4
Email:Password 5`
var words = str.split('\n');
 let random = words[Math.floor(Math.random()*words.length)];
message.author.send(`**__Fortnite Account__**  **__\n ${random}__**`)```
 It is random so I want like if you generate with .gen fortnite and you get Email:Password 4 I want it so if you gen like 10 more times you wont get the same one because the system deletes it. THen I need helping making it so when someone does .gen fortnite it Makes stock -1