module.exports.run = async (bot, message, args) => {
let ticketreason = args[1];
let ticketname = \"ticket\" + ticketreason;
message.guild.createChannel
You can do this by checking for the id. While this might not resolve this particular issue, it might help others with a similar issue.:
var chan_id;
if(message.guild.channels.cache.get(chan_id) === undefined) {
//checks if the channel doesn't exist
//put the action to take here
}
//continue your code here