diff --git a/ros_web_api_bellande_step/launch/bellande_step_api_2d.launch.py b/ros_web_api_bellande_step/launch/bellande_step_api_2d.launch.py
index c235410..d6e8a89 100644
--- a/ros_web_api_bellande_step/launch/bellande_step_api_2d.launch.py
+++ b/ros_web_api_bellande_step/launch/bellande_step_api_2d.launch.py
@@ -8,7 +8,7 @@ def ros1_launch_description():
     args = sys.argv[1:]
 
     # Construct the ROS 1 launch command
-    roslaunch_command = ["roslaunch", "ros_web_api_bellande_step", "bellande_step_api_2d.py"] + args
+    roslaunch_command = ["roslaunch", "ros_web_api_bellande_step", "bellande_step_api_2d.launch"] + args
 
     # Execute the launch command
     subprocess.call(roslaunch_command)
diff --git a/ros_web_api_bellande_step/src/bellande_step_api_2d.py b/ros_web_api_bellande_step/src/bellande_step_api_2d.py
index 2adefa4..118edce 100755
--- a/ros_web_api_bellande_step/src/bellande_step_api_2d.py
+++ b/ros_web_api_bellande_step/src/bellande_step_api_2d.py
@@ -18,11 +18,11 @@ def main():
         endpoint_path = config['endpoint_path']["2d"]
     
     # Get the parameters from the ROS parameter server
-    x1 = rospy.get_param('x1')
-    y1 = rospy.get_param('y1')
-    x2 = rospy.get_param('x2')
-    y2 = rospy.get_param('y2')
-    limit = rospy.get_param('limit')
+    x1 = rospy.get_param('x1', 0)
+    y1 = rospy.get_param('y1', 0)
+    x2 = rospy.get_param('x2', 0)
+    y2 = rospy.get_param('y2', 0)
+    limit = rospy.get_param('limit', 3)
 
     # JSON payload
     payload = {
@@ -47,6 +47,7 @@ def main():
         response.raise_for_status()  # Raise an error for unsuccessful responses
         data = response.json()
         print("Next Step:", data['next_step'])
+    
     except requests.exceptions.RequestException as e:
         print("Error:", e)
 
@@ -55,6 +56,6 @@ if __name__ == '__main__':
     if ros_version == "1":
         import rospy
     elif ros_version == "2":
-        rclpy
+        import rclpy
 
     main()