Don't know how to change to lowercase in this scenario

Question

I am trying to use the discord.js awaitMessages method but it doesn't seem to work with uppercase letters because my possible answers (triviacharacterslist.js) are all lowercase. I tried to convert this (in the code) but it doesn't seem to work.

triviachar.js:

const iKF = Characters.KiritoVariants;
        const possibleAnswers = [iKF.kirito0, iKF.kirito1, iKF.kirito2, iKF.kirito3, iKF.kirito4, iKF.kirito5, iKF.kirito6, iKF.kirito7, iKF.kirito8];
        const triviaKiritoEmbed = new MessageEmbed()
            .setColor('#008fff')
            .setTitle(guessCharacterString)
            .setImage(Characters.CharacterImgs.kiritoimg)
    
        msg.channel.send(triviaKiritoEmbed)

        const filterK = m => possibleAnswers.some(answer => m.content.includes(answer));
        msg.channel.awaitMessages(filterK, { max: 1, time: 15000, errors: ['time'] })
        .then(collected => {switch(collected.first().content.toLowerCase()){
            case Characters.KiritoVariants.kirito0:
                msg.channel.send(fivePoint);
                break;
            case Characters.KiritoVariants.kirito3:
                msg.channel.send(fivePoint);
                break;
            case Characters.KiritoVariants.kirito6:
                msg.channel.send(fivePoint);
                break;
            case Characters.KiritoVariants.kirito1:
                msg.channel.send(tenPoint);
                break;
            case Characters.KiritoVariants.kirito2:
                msg.channel.send(tenPoint);
                break;
            case Characters.KiritoVariants.kirito4:
                msg.channel.send(tenPoint);
                break;
            case Characters.KiritoVariants.kirito5:
                msg.channel.send(tenPoint);
                break;
            case Characters.KiritoVariants.kirito7:
                msg.channel.send(tenPoint);
                break;
            case Characters.KiritoVariants.kirito8:
                msg.channel.send(tenPoint);
                break;
        }})
        .catch(collected => msg.channel.send('too bad u took too long ya 3am'));
    }

triviacharacterslist.js:

//character names ---------------------------------------------------------------------------------------------------------------

const KiritoVariants = {
    kirito0: 'kirito',
    kirito1: 'kirito sao',
    kirito2: 'kirito sword art online',
    kirito3: 'kazuto',
    kirito4: 'kazuto sao',
    kirito5: 'kazuto sword art online',
    kirito6: 'kazuto kirigaya',
    kirito7: 'kazuto kirigaya sao',
    kirito8: 'kazuto kirigaya sword art online'
};

Answer 1

I think @Zsolt had the right idea but the execution is a bit wrong. Since all your answers are already in lowercase, calling .toLowerCase() on an answer string won't do much. Instead, you need to call .toLowerCase() on the string content. See the example below:

const filterK = m => possibleAnswers.some(answer => m.content.toLowerCase().includes(answer));