TypeError: (intermediate value)._patchPlaylist is not a function

Question

I've got error message like "TypeError: (intermediate value)._patchPlaylist is not a function" on console log. Please check out what's wrong from my script:

        const playlist = new distube_1.Playlist(playlistInfo);
        const fetchTheRest = async (q, fs, us = false) => {
            if (queries.length) {
                let results = [];
                if (this.parallel) {
                    results = await Promise.all(queries.map(query => this.search(query)));
                }
                else {
                    for (let i = 0; i < queries.length; i++) {
                        results[i] = await this.search(queries[i]);
                    }
                }
                playlist.songs = results
                    .filter((r) => !!r)
                    .map(r => new distube_1.Song(r, member)._patchPlaylist(playlist));
                q.addToQueue(playlist.songs, skip ? 1 : us ? 2 : -1);
            }
            playlist.songs.unshift(fs);
        };

How I can fix it? thanks for help me.