Query Execution not working on docker scylla

[sujit-baniya]

Platform: Linux (Docker)
App Language: Golang (non-Docker)
I'm trying to use this driver for operations but got stuck on error

panic: node &{[220 47 239 56 226 129 69 100 158 115 200 137 86 16 55 196] 172.21.0.2 datacenter1 rack1 <nil> {[] {[] 0}}} is down

Code:

package main

import (
	"context"
	"fmt"

	"github.com/scylladb/scylla-go-driver"
)

func main() {
	var Keyspace = "go_demo1"
// 	var Port = 9042
	var Host = "127.0.0.1"
	ctx := context.Background()
	cfg := scylla.DefaultSessionConfig(Keyspace, []string{Host}...)
	session, err := scylla.NewSession(ctx, cfg)
	if err != nil {
		panic(err)
	}
	defer session.Close()
	stmts := []string{
		"CREATE KEYSPACE IF NOT EXISTS go_demo1 WITH replication = {'class': 'SimpleStrategy', 'replication_factor' : 1}",
		"CREATE TABLE IF NOT EXISTS go_demo1.users (user_id int, fname text, lname text, PRIMARY KEY((user_id)))",
		"INSERT INTO go_demo1.users(user_id, fname, lname) VALUES (1, 'rick', 'sanchez')",
		"INSERT INTO go_demo1.users(user_id, fname, lname) VALUES (4, 'rust', 'cohle')",
	}

	for _, stmt := range stmts {
		q := session.Query(stmt)
		if _, err := q.Exec(ctx); err != nil {
			panic(err.Error())
		}
	}

	q := session.Query("SELECT * FROM go_demo1.users")

	res, err := q.Exec(ctx)
	if err != nil {
		panic(err)
	}

	for _, row := range res.Rows {
		pk, err := row[0].AsInt32()
		if err != nil {
			panic(err)
		}
		name, err := row[1].AsText()
		if err != nil {
			panic(err)
		}
		surname, err := row[2].AsText()
		if err != nil {
			panic(err)
		}
		fmt.Println(pk, name, surname)
	}
}

The driver is not respecting the exported port.