kill processes from docker-compose "container_name"

Context : 

follwing a project-name change -> renaming the directory-name/docker-compose.yml the processes that were started by docker-compose were duplicated.

From the new project :

*  impossible to see them.

From docker ps : no process listed

From OS perspective ps aux : process present.

Test 1 : kill them all !

 Step 1 : identify them

ps aux | grep $(echo "$(grep container_name docker-compose.yml | grep -v '#' | awk '{printf("%s\\|", $2)}')grep")

Step 2 : kill -9 them all

ps aux | grep $(echo "$(grep container_name docker-compose.yml | grep -v '#' | awk '{printf("%s\\|", $2)}')grep") | awk '{print $2}' | xargs sudo kill -9

-> result : when restarting docker, they're back :-( 

Test 2 : stop docker + docker-compose start

apparently working, but I lost my container's content...