Tolerance Issues with MoveIt in Gazebo

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I am working with the MoveIt Motion Planning tool to control a manipulator robot with 6 degrees of freedom. When I do the simulation only with RViz, the target positions are always reached, but when I use it with Gazebo, the robot does not manage to reach the desired position, I want to believe that it is due to the fact that there is gravity in Gazebo, does anyone know how I can correct this problem or increase the precision of my robot's movements (without disabling physics)? Motion Planning always says that the plan failed because the position is out of tolerance.

Should I modify the URDF of the robot or some config file? I used MoveIt Setup Assitant to create my robot's support package.