Found Empty jointstate message

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Hi, I am currently working on iiwa lbr arm in ros and using compute_ik service to calculate the inverse kinematics and send the joint state message to /joint_state topic, which unity in windows is subscribe to this topic through rosbridge. I wrote the script to basically publish the joint state part of the IK solution to /joint_state. However, while it does give me a response with error_code 1 which I believe it means it is successful, it keeps giving me Found Empty jointstate message error, what exactly could be causing it? my setup is a robot arm mounted upside down and the values I am giving it to compute IK solution is: [0.2 0.3 0.1 0.0 30.0 0.0], and here is my code to get IK solution in python:

def IK_compute(data):
    global JointPub
    #Wait for theIK service to become available
    rospy.wait_for_service('compute_ik')
    #rospy.init_node('service_query')
    #Construct the request
    request = GetPositionIKRequest()
    request.ik_request.group_name = "kuka_iiwa"
    request.ik_request.attempts = 20
    request.ik_request.pose_stamped.header.frame_id = "base"

    #Set the desired orientation for the end effector HERE
    request.ik_request.pose_stamped.pose.position.x = data[0]
    request.ik_request.pose_stamped.pose.position.y = data[1]
    request.ik_request.pose_stamped.pose.position.z = data[2]

    q = quaternion_from_euler(np.deg2rad(data[3]), np.deg2rad(data[4]), np.deg2rad(data[5]))
    request.ik_request.pose_stamped.pose.orientation = Quaternion(*q)

    #Create the function used to call the service
    compute_ik = rospy.ServiceProxy('compute_ik', GetPositionIK)
    try:
        #Send the request to the service
        response = compute_ik(request)
        #response.solution.joint_state.velocity = [0, 0, 0, 0, 0, 0, 0]
        #response.solution.joint_state.effort = [0, 0, 0, 0, 0, 0, 0]
        print(response)
        JointPub.publish(response.solution.joint_state)
        '''
        if response.error_code == 1:
            print("success")
        elif response.error_code == -31:
            print("NO IK solution")
        '''
    except  rospy.ServiceException, e:
        print "Service callfailed: %s"%e

and my terminal loginfo are:

[INFO] [1613099932.751784]: solution:
  joint_state:
    header:
    seq: 0
    stamp:
        secs: 0
        nsecs:      0
    frame_id: "/world"
    name: [joint_a1, joint_a2, joint_a3, joint_a4, joint_a5, joint_a6, joint_a7]
    position: [-0.1507822277522531, 2.0425807428651455, 1.1103473810090956, -1.9972497454495166, 1.449649742196664, 1.9401822415585879, 1.2651551284903115]
    velocity: []
    effort: []
  multi_dof_joint_state:
    header:
    seq: 0
    stamp:
        secs: 0
        nsecs:      0
    frame_id: "/world"
    joint_names: []
    transforms: []
    twist: []
    wrench: []
  attached_collision_objects: []
  is_diff: False
error_code:
  val: 1

for an example IK response and

[ERROR] [1613099932.525326494]: Found empty JointState message

For a sample error message from rviz Any help will be appreciated!