error loading <rosparam> file does not exist

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I am facing a problem with loading a yaml file to robot_localization node. I am pretty sure of the path and the name of the file as there are multiple other parameters file and they all loaded just fine. I don't have a clue where this error comes from if anyone can help please do not hesitate. This the error when I launch:

RLException: error loading <rosparam> tag: 
file does not exist [/home/moo/catkin_ws/src/mobile_robot_autonomous_navigation/param/ekff.yaml)]
XML is <rosparam command="load" file="$(find mobile_robot_autonomous_navigation)/param/ekff.yaml)"/>
The traceback for the exception was written to the log file

launch file:

<?xml version="1.0"?>
<launch>

  <arg name="map_file" default="$(find mobile_robot_autonomous_navigation)/maps/alexa_map.yaml"/>
  <arg name="model" default="$(find kandb)/urdf/new_urdf.urdf.xacro"/>

  <rosparam file="$(find mobile_robot_autonomous_navigation)/param/controllers.yaml" command="load"/>
  <rosparam file="$(find mobile_robot_autonomous_navigation)/param/joint_limits.yaml" command="load"/>

  <param name="robot_description" command="$(find xacro)/xacro $(arg model)" />

  <node name="robot_hardware_interface" pkg="mobile_robot_autonomous_navigation" type="mobile_robot_hardware_interface" output="screen">
    <remap from="/mobile_robot/mobile_base_controller/cmd_vel" to="/cmd_vel"/>
   </node>

  <node name="robot_state_publisher" pkg="robot_state_publisher" type="robot_state_publisher" >
  </node>

  <node pkg="tf" type="static_transform_publisher" name="map_to_base_footprint" 
  args="0.0 0.0 0.0 0.0 0.0 0.0 /base_footprint /base_link 10" />

  <node name="rviz" pkg="rviz" type="rviz" args="-d $(find mobile_robot_autonomous_navigation)/param/nav_config.rviz"/>

  <node name="controller_spawner" pkg="controller_manager" type="spawner" respawn="false" output="screen"
        args="
            /mobile_robot/joints_update
            /mobile_robot/mobile_base_controller" >
  </node>

  <node name="imu_node" pkg="mpu_6050_driver" type="imu_node.py" >
  </node>

  <node name="imu_filter_node_for_orientation" pkg="imu_complementary_filter" type="complementary_filter_node" >
  </node>

  <node pkg="robot_localization" type="ekf_localization_node" name="ekf_se">
    <rosparam command="load" file="$(find mobile_robot_autonomous_navigation)/param/ekff.yaml)"/>
    <remap from="odometry/filtered" to="odom"/>
  </node>

  <node name="map_server" pkg="map_server" type="map_server" args="$(arg map_file)" >
  </node>

  <include file="$(find ydlidar_ros)/launch/X4.launch" />
  <include file="$(find mobile_robot_autonomous_navigation)/launch/amcl.launch" />
  <include file="$(find mobile_robot_autonomous_navigation)/launch/move_base.launch" /> 
 <!--<include file="$(find rf2o_laser_odometry)/launch/rf2o_laser_odometry.launch" /> -->

</launch>