Rviz Marker not receving any published data

edit

Hello everyone i am trying to draw bounding boxes on my pointcloud i was able to write the code and it compiles without any error but i am having a problem the topic bounding_box i created when i want to check it with rostopic echo it doesn"t have any published data

here is a sample of my code

import time
import sys
import pyntcloud
import rospy
import sensor_msgs.point_cloud2
from sensor_msgs.msg import PointCloud2
from visualization_msgs.msg import Marker
from visualization_msgs.msg import MarkerArray

class marker() :
    def __init__(self):
        self.pt_x=0
        self.pt_y=0
        self.pt_z=0
        self.pt_i=0
        self.points=[]

    self.pub = rospy.Publisher("/bounding_box", Marker, queue_size = 100)
    rospy.sleep(1)
def point_cloud(self,msg):
    print(msg.header.seq)
    self.points=sensor_msgs.point_cloud2.read_points(msg, skip_nans=True)
    for point in sensor_msgs.point_cloud2.read_points(msg, skip_nans=True):
        self.pt_x = point[0]
        self.pt_y = point[1]
        self.pt_z = point[2]
        self.pt_i = point[3]

def main(self):
    rospy.Subscriber("/ti_mmwave/radar_scan_pcl_0", PointCloud2, self.point_cloud)
    x = [self.pt_x]
    y = [self.pt_y]
    z = [self.pt_z]
    if self.points != []:
        centroid = (sum(x) / len(self.points), sum(y) / len(self.points),sum(z) / len(self.points))
        marker = Marker()
        marker.header.frame_id = "/map"
        marker.type = marker.CUBE
        marker.action = marker.ADD
        marker.pose.orientation.x = 0
        marker.pose.orientation.y = 0
        marker.pose.orientation.z = 0
        marker.pose.orientation.w = 1
        marker.pose.position.x = centroid[0]
        marker.pose.position.y = centroid[1]
        marker.pose.position.z = centroid[2]
        t = rospy.Duration()
        marker.lifetime = t
        marker.scale.x = 1
        marker.scale.y = 1
        marker.scale.z = 1
        marker.color.a = 1
        marker.color.r = 1.0
        self.pub.publish(marker)
        rate = rospy.Rate(5)
        rate.sleep()
    rospy.spin()

if __name__ == '__main__':
    rospy.init_node("bounding_box")
    x=marker()
    x.main()

i would appreciate any help thank you a lot