bag file and tf transformation

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HI,

I recorded a bag file of my robot and this bag file contains all the topics. From this data I need to transform messages from laser-scanner to odom frame using the time stamp when the bag created. What i did is I used the tf and tf_static topics and put them in a buffer and then tried to transform between frames but i am still getting an error :

[WARN][/G2O_Generator][1568971858.801114]: Lookup would require extrapolation into the past. Requested time 1568786441.083348989 but the earliest data is at time 1568786624.298866987, when looking up transform from frame [nav350] to frame [odom]

And this is the part of my code that does this :

 import rospy
import rosbag
from world_model_conversions.sensor_msgs_conversions import vector_list_from_cloud_msg
import tf2_ros
import tf
import tf2_py as tf2
import numpy
from std_msgs.msg import Header
from tf2_geometry_msgs import PointStamped
from tf2_sensor_msgs.tf2_sensor_msgs import do_transform_cloud
from geometry_msgs.msg import Pose, Point, Quaternion


class G2O_Generator(object):
    def __init__(self):
        self._tf_buffer = tf2_ros.Buffer()
        self._tf_listener = tf2_ros.TransformListener(self._tf_buffer)

    def convert_pointcloud_frame(self, bag_name):
        #fill the buffer with tf and tf_static msgs
        bag = rosbag.Bag(bag_name)
        for topic, msg, t in bag.read_messages(topics=['/tf', '/tf_static']):
            for msg_tf in msg.transforms:
                self._tf_buffer.set_transform(msg_tf,'default_authority')

        bag = rosbag.Bag(bag_name)
        for topic, msg, t in bag.read_messages(topics=['/reflector_cloud']):
            reflector_cloud_msgs = msg
            trans = self._tf_buffer.lookup_transform("odom", reflector_cloud_msgs.header.frame_id,
                                                     reflector_cloud_msgs.header.stamp,
                                                     rospy.Duration(1))

            cloud_out = do_transform_cloud(reflector_cloud_msgs, trans)
            print ("pint_cloud", cloud_out)

        bag.close()


if __name__ == '__main__':
    rospy.init_node('G2O_Generator')
    m = G2O_Generator()
    m.convert_pointcloud_f