[Vuejs]-Laravel echo event broadcasting with pusher and vueJS is not working like written in the docs

If you want to use template literals they should be between backticks, not single quotes, so you should be subscribing to:

Echo.join(`room.${roomId}`)
    .here(...)
    .joining(...)
    .leaving(...)
    .listen('NewMessage', (e) => {
        //
});