I am currently trying to do a cooldown, the code is not mine, but would like to understand why I am getting this error and wonder how to fix it

const cooldowns = new Map();

if(cooldowns.has(command.name)) {
    cooldowns.set(command.name, new Discord.Collection())
}

const current = Date.now()
const time_stamps = cooldowns.get(command.name)
const cooldown = (command.cooldown) * 1000;

if(time_stamps.has(message.author.id)) {
    const expiration = time_stamps.get(message.author.id) + cooldown

    if(current < expiration) {
        const time = (expiration - current) / 1000;
        return message.reply("message")
    }
}
time_stamps.set(message.author.id, current);
setTimeout(() => time_stamps.delete(message.author.id), cooldown);

Error:

if(time_stamps.has(message.author.id)) {
               ^
TypeError: Cannot read properties of undefined (reading 'has')