ROS_DISTRO make sure environment doesn't mix paths

I get this message every time I source the ws, but I don’t know how to check this.

user:~$ source /opt/ros/foxy/setup.bash
ROS_DISTRO was set to ‘noetic’ before. Please make sure that the environment does not mix paths from different distributions.

Hello @JohnRJennings ,

Don’t worry about this message. It’s just a warning since you are changing your environment from ROS1 to ROS2.