understanding tf with move_base

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Hi! I'm writing a node, that should allow my turtlebot3_waffle to move to ar_tag, sending tf between base_link and ar_Tag as a goal to move_base. But, after launching this node I have this:

[ WARN] [1553587624.636453683, 2739.978000000]: Clearing costmap to unstuck robot (3.000000m).
[ WARN] [1553587637.825312516, 2745.080000000]: Rotate recovery behavior started.
[ WARN] [1553587662.356952081, 2756.631000000]: Clearing costmap to unstuck robot (1.840000m).
[ WARN] [1553587673.253428778, 2761.732000000]: Rotate recovery behavior started.
[ERROR] [1553587684.935379862, 2766.931000000]: Aborting because a valid plan could not be found. Even after executing all recovery behaviors

this is my code:

#!/usr/bin/env python  
import rospy

import math
import tf2_ros
import geometry_msgs.msg
import actionlib
from move_base_msgs.msg import MoveBaseAction, MoveBaseGoal


def move_base(bar_x, bar_y):

    client = actionlib.SimpleActionClient('move_base', MoveBaseAction)
    client.wait_for_server()

    goal = MoveBaseGoal()
    goal.target_pose.header.frame_id = "base_link"
    goal.target_pose.header.stamp = rospy.Time.now()
    goal.target_pose.pose.position.x = bar_x
    goal.target_pose.pose.position.y = bar_y
    goal.target_pose.pose.position.z = 0
    goal.target_pose.pose.orientation.w = 1
    client.send_goal(goal)
    wait = client.wait_for_result()
    if not wait:
        rospy.logerr("Action server not available!")
        rospy.signal_shutdown("Action server not available!")
    else:
        return client.get_result()


if __name__ == '__main__':
    try:
        rospy.init_node('ar_tag_navigation')

        tfBuffer = tf2_ros.Buffer()
        listener = tf2_ros.TransformListener(tfBuffer)



        rate = rospy.Rate(10.0)
        while not rospy.is_shutdown():
            try:
                trans = tfBuffer.lookup_transform('base_link', 'ar_marker_0', rospy.Time())
            except (tf2_ros.LookupException, tf2_ros.ConnectivityException, tf2_ros.ExtrapolationException):
                rate.sleep()
                continue

            BAr_X = trans.transform.translation.x
            BAr_Y = trans.transform.translation.y

            result = move_base(BAr_X, BAr_Y)
            if result:
                rospy.loginfo("Goal execution done!")
    except rospy.ROSInterruptException:
        rospy.loginfo("Navigation test finished.")

I realy don't know what is wrong. I saw tf tree and it's ok