Regarding the process, do ps auxf | grep cardano-node
In case there is still a process running do killall cardano-node to kill the process.
If you are using systemd (systemctl) to manage the cardano-node process, you can set that in the config file. See if you have /etc/systemd/system/cardano-node maybe (cnode) or something similar and set it like:
TimeoutStopSec=30
in the [Service] section.