Installation problem: Gazebo namespace occupied

[lgulyas1972]

I am trying to install Revolve on Ubuntu version: 20.04 (VirtualBox 7.0.12).
I attempt to do: Minimal installation.

However, installation fails with a namespace problem:

/home/erik/UNI_project/revolve/cpprevolve/revolve/gazebo/brains/BrainFactory.cpp:25:22: error: ‘namespace gz = gazebo;’ conflicts with a previous declaration
   25 | namespace gz = gazebo;
      |                      ^
In file included from /usr/include/ignition/math6/gz/math/Helpers.hh:34,
                 from /usr/include/ignition/math6/gz/math/Spline.hh:22,
                 from /usr/include/ignition/math6/ignition/math/Spline.hh:18,
                 from /usr/include/gazebo-11/gazebo/common/Animation.hh:22,
                 from /usr/include/gazebo-11/gazebo/common/common.hh:5,
                 from /home/erik/UNI_project/revolve/cpprevolve/revolve/gazebo/brains/BrainFactory.h:27,
                 from /home/erik/UNI_project/revolve/cpprevolve/revolve/gazebo/brains/BrainFactory.cpp:22:
/usr/include/ignition/math6/gz/math/config.hh:23:11: note: previous declaration ‘namespace gz { }’
   23 | namespace gz
      |           ^~

Any ideas will be appreciated.