Having issues writing to a JSON file, after reading it (discord.js)

I've been working on a project for a friend's discord server, where I want to keep sort of a 'database' on our members, like a warning (or strike) count, their age (because we've been having issues with underage members) and some notes. I've been using tutorials as I'm pretty new to javascript, and really new to Discord.js, so, I'm not really sure on what I'm doing yet.

(to clarify, I'm not getting any errors, it's just not updating to the new file)

Here are the resources I've used:

https://www.youtube.com/watch?v=JB1rWJRafRA

https://discordjs.guide/popular-topics/collectors.html#message-collectors

https://www.youtube.com/watch?v=J2bKyv5pp-M

And my code: (sorry in advance, it's really messy)

const Discord = require('discord.js');
const fs = require('fs');
const jsonfile = require('jsonfile');
const Client = new Discord.Client();

var data = {}; //start of member activeness tracker
if (fs.existsSync('data.json')) {
    data = jsonfile.readFileSync('data.json');
}

console.log("Bot Starting...");

Client.on("ready", () => console.log('ServerMgr is ready!  Now managing servers!'));  //bot init complete

Client.on("message", (message) =>  {

    if (message.guild.id in data === false) {data[message.guild.id] = {} } //if new guild

    const guildData = data[message.guild.id];

    if (message.author.id in guildData === false) {
        guildData[message.author.id] = {
            username: message.author.username,
            message_count: 0,
            last_message: 0,
            age: 0,
            times_left: 0,
            strikes: 0,
            notes: ""
         }
    }

    const userData = guildData[message.author.id];
    userData.message_count ++
    userData.last_message = Date.now();

    jsonfile.writeFileSync('data.json', data)

    const parts = message.content.split(' ') 
    if(parts[0] === ';ping') {message.reply('```SeverMgr is online!\nCurrent Ping: ' + (Math.abs(Date.now() - message.createdTimestamp))/ 100 + " ms```")}
    if(parts[0] === ';read') {
        if (message.mentions.members.first()) {
            var user = message.mentions.users.first()
            const id = user.id
            const userData = guildData[id]
            const lastMessage = new Date(userData.last_message)
            message.channel.send("Getting data for " + user.username + "#" + user.discriminator + "...")
            message.channel.send("Sent " + userData.message_count + " messages\n" + 
            "Last message was sent at: " + lastMessage + "\n" +
            "Age: " + userData.age + "\n" + 
            "Times user left server: " + userData.times_left + "\n" +
            "Strikes: " + userData.strikes + "\n" + 
            userData.notes);

        } else {
        message.reply("You need to mention a user to get their data!");
        }
    }

    if(parts[0] === ';write') {
        if (message.mentions.members.first()) {

            var user = message.mentions.users.first();
            const id = user.id;
            const userData = guildData[id];

            message.channel.send("What data point do you want to edit? \n Accepted responses are: \n `message count` \n `age` \n `times left` \n `strikes` \n `notes` ")
            let filter = m => m.content.includes('message count' || 'age' || 'times left' || 'strikes' || 'notes') && !m.author.bot ;
            let collector = new Discord.MessageCollector(message.channel, filter);

    collector.on('collect', (m,col) => {
        var res = "";
        let mess = m.content;
        console.log(mess);
        if (mess == ("message count")) {res = 'message_count' } 
        if (mess == ("age")) {res = 'age' }
        if (mess == ("times left")) {res = 'times_left' }
        if (mess == ("strikes")) {res = 'strikes' }
        if (mess == ("notes")) {res = 'notes' }
        console.log(res);
        message.channel.send("Editing " + res + "\n The current value is:");

        if (res == "message count") {message.channel.send(userData.message_count) } 
        if (res == "age") {message.channel.send(userData.age)}
        if (res == "times left") {message.channel.send(userData.times_left)}
        if (res == "strikes") {message.channel.send(userData.strikes)}
        if (res == "notes") {message.channel.send(userData.notes)}

        collector.stop();
        message.channel.send("The value currently located inside of " + res + " will be overwritten, so if you want to edit the content directly, copy the message above, and paste it into the send box.");
        let filter = m => !m.author.bot;
        let collector2 = new Discord.MessageCollector(message.channel, filter);
    });

    collector2.on('collect', m => {
        var mess = m.content;
        if (res === "message count") {userData.message_count = mess } 
        if (res == "age") {userData.age = mess}
        if (res == "times left") {userData.times_left = mess}
        if (res == "strikes") {userData.strikes = mess}
        if (res == "notes") {userData.notes = mess}
        message.channel.send("Data saved!");
        console.log("Saving " + mess);
    
        var guildData = data[message.guild.id];
        var userData = guildData[message.author.id];
        var pointData = userData[res];
        console.log("old data");
        console.log(pointData);
        pointData = mess;
        console.log("new data");
        console.log(pointData);
        jsonfile.writeFileSync('data.json', data) //HERE IS THE ISSUE
        collector2.stop();
    });

    } else {
        message.reply("You need to mention a user to edit their data!");
    }
}
});

Client.login('TOKEN');

The data is stored as such:

'779904676879007744': {
    username: 'SeverMgr',
    message_count: 129,
    last_message: 1606028233445,
    age: 0,
    times_left: 0,
    strikes: 0,
    notes: ''

Thanks for any help!