As you can see from the message, there’s already a Jupyter Notebook running in Port 8888, hence a new Notebook instance is started in 8889. I suspect you are tunneling port 8888 and not 8889 in your ssh syntax (please share your ssh syntax here to verify). Make sure you are tunneling port similar to - ssh -i <pem key> ubuntu@<ec2...> -L 8888:localhost:8888
Type - jupyter notebook list on your AWS terminal. This should show you that notebook running in 8888. If that doesn’t resolve it, restart your AWS machine and see if that fixes it (meaning kills the process that’s holding port 8888 in AWS - which most likely is another jupyter notebook).
while i’m launching jupyter notebook it displaying (copy the url with token on my local browser) by the way i’m not using Aws or putty. how to resolve this problem ?