diff --git a/crazyflie/scripts/crazyflie_server.py b/crazyflie/scripts/crazyflie_server.py
index a47c9c896..138dc6bf8 100755
--- a/crazyflie/scripts/crazyflie_server.py
+++ b/crazyflie/scripts/crazyflie_server.py
@@ -802,22 +802,22 @@ def _upload_trajectory_callback(self, request, response, uri="all"):
         
         id = request.trajectory_id
         offset = request.piece_offset
-        size = request.pieces.size()
+        lenght = len(request.pieces)
         total_duration = 0
-        self.get_logger().info("upload_trajectory(id=%d,offset=%d, size=%d)"% (
+        self.get_logger().info("upload_trajectory(id=%d,offset=%d, lenght=%d)"% (
                 id,
                 offset,
-                size,
+                lenght,
             ))
 
         trajectory = []
-        for i in range(size):
+        for i in range(lenght):
             piece = request.pieces[i]
-            px = piece.poly_x
-            py = piece.poly_y
-            pz = piece.poly_z
-            pyaw = piece.poly_yaw
-            duration = request.duration.sec
+            px = Poly4D.Poly(piece.poly_x)
+            py = Poly4D.Poly(piece.poly_y)
+            pz = Poly4D.Poly(piece.poly_z)
+            pyaw = Poly4D.Poly(piece.poly_yaw)
+            duration = piece.duration.sec
             trajectory.append(Poly4D(duration, px, py, pz, pyaw ))
             total_duration = total_duration + duration
         
@@ -864,9 +864,9 @@ def _start_trajectory_callback(self, request, response, uri="all"):
             ))
         if uri == "all":
             for link_uri in self.uris:
-                self.swarm._cfs[link_uri].cf.commander.start_trajectory(id, ts, rel, rev, gm)              
+                self.swarm._cfs[link_uri].cf.high_level_commander.start_trajectory(id, ts, rel, rev, gm)              
         else:
-            self.swarm._cfs[uri].cf.commander.start_trajectory(id, ts, rel, rev, gm)              
+            self.swarm._cfs[uri].cf.high_level_commander.start_trajectory(id, ts, rel, rev, gm)              
 
         return response