/odometer/filtered increases instantly, how to fix it?

edit

hi As I checked the output of /odometry/filtered topic, which comes from the fusion of Imu (/gx5/imu/data) and wheel odometer (/warthog_velocity_controller/odom), I have noticed that even when the vehicle has stopped in one location, it keeps increasing in terms of position and covariance. I have atached the output of the topics.

masoumeh@masoumeh-ThinkPad-T490s:~/catkin_ws$ rostopic echo -n1 /odometry/filtered 
header: 
  seq: 16342
  stamp: 
    secs: 1633620970
    nsecs: 432253599
  frame_id: "odom"
child_frame_id: "base_link"
pose: 
  pose: 
    position: 
      x: -0.186495242275
      y: 0.523015456229
      z: 0.0
    orientation: 
      x: 0.0
      y: 0.0
      z: 0.817129320265
      w: 0.576454398858
  covariance: [16.415020500015576, 0.0002285947704235223, 0.0, 0.0, 0.0, -1.2445824258342931e-06, 0.00022859477042352425, 16.41445947704145, 0.0, 0.0, 0.0, -4.43159366258407e-07, 0.0, 0.0, 3.3323070839954904e-07, -4.5684625048115965e-22, -9.603536954033966e-18, 0.0, 0.0, 0.0, -4.568462504811598e-22, 3.3312820969750064e-07, -4.274974999686913e-29, 0.0, 0.0, 0.0, -9.60353695403397e-18, -4.275266519602526e-29, 3.3312820969750064e-07, 0.0, -1.2445824258342934e-06, -4.431593662584071e-07, 0.0, 0.0, 0.0, 0.0029477080077202527]
twist: 
  twist: 
    linear: 
      x: 0.0100789939236
      y: 0.0
      z: 0.0
    angular: 
      x: 0.0
      y: 0.0
      z: 0.00252659512872
  covariance: [0.001389703408756552, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0014353813879710376, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 3.331794432899336e-07, -1.2587718330029596e-31, -2.6229314325426267e-27, 0.0, 0.0, 0.0, -1.2587718330029607e-31, 3.327194703607173e-07, -4.6471326256187006e-38, 0.0, 0.0, 0.0, -2.6229314325426292e-27, -4.647454171027039e-38, 3.327194703607173e-07, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0017372010630630486]

……………………………………………………………………………………………………

masoumeh@masoumeh-ThinkPad-T490s:~/catkin_ws$ rostopic echo -n1 /odometry/filtered 
header: 
  seq: 43395
  stamp: 
    secs: 1633621513
    nsecs: 337227583
  frame_id: "odom"
child_frame_id: "base_link"
pose: 
  pose: 
    position: 
      x: -0.498594230072
      y: 1.39685559327
      z: 0.0
    orientation: 
      x: 0.0
      y: 0.0
      z: 0.817659281694
      w: 0.575702439685
  covariance: [43.5910138933412, 0.0006113355352029022, 0.0, 0.0, 0.0, -1.2759836072195995e-06, 0.0006113355352029041, 43.589520650583054, 0.0, 0.0, 0.0, -4.56985891525322e-07, 0.0, 0.0, 3.3323032323385704e-07, -5.611853376685535e-22, -1.0711948372335473e-17, 0.0, 0.0, 0.0, -5.611853376685536e-22, 3.3312744034408844e-07, -5.835691885062672e-29, 0.0, 0.0, 0.0, -1.0711948372335473e-17, -5.835762457675017e-29, 3.3312744034408844e-07, 0.0, -1.2759836072196e-06, -4.5698589152532204e-07, 0.0, 0.0, 0.0, 0.0029195771498232597]
twist: 
  twist: 
    linear: 
      x: 0.0110216489819
      y: 0.0
      z: 0.0
    angular: 
      x: 0.0
      y: 0.0
      z: 0.00283324487967
  covariance: [0.0015144997873774034, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.001568887802757938, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 3.331788659065427e-07, -1.547985581602241e-31, -2.9369963439340677e-27, 0.0, 0.0, 0.0, -1.547985581602242e-31, 3.327171745332632e-07, -6.37250333683801e-38, 0.0, 0.0, 0.0, -2.9369963439340695e-27, -6.372578879917173e-38, 3.327171745332632e-07, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0017363589240245616]

…………………………………………………………………………………………………

masoumeh@masoumeh-ThinkPad-T490s:~/catkin_ws$ rostopic echo -n1 /warthog_velocity_controller/odom 
header: 
  seq: 20099
  stamp: 
    secs: 1633621647
    nsecs: 353004821
  frame_id: "odom"
child_frame_id ...