ModuleNotFoundError: No module named 'services_quiz' Problem in Quiz 6.4

Unfortunately, the image you shared was too small and I could not see it clearly.

In any case, what is probably happening is that you have not set up your messages correctly. Can you check that the messages are built by running:

rossrv list | grep BB8

You should find a custom message like:

services_quiz/BB8CustomServiceMessage

If you can find the message, please show the output of the commands above.

If you can’t find it, please go over how to add a custom service message again and modify your package accordingly, then:

cd ~/catkin_ws
rm -rf build/ devel/
catkin_make
source devel/setup.bash