Unable to SSH into Server

[techlists at phpcoderusa.com]

Hi,

I am a little stuck.

I am trying to configure a user that will allow me to log into an Ubuntu 
24.04lts server via SSH.

I created a line : "AllowUsers default" in /etc/ssh/sshd_config

Then sudo systemctl restart ssh

Try to login and get "client_loop: send disconnect: Broken pipe"

sudo tail /var/log/faillog returns nothing.

I can SSH into the server from my Kubuntu desktop under the default user 
created during server o/s install

A search says it is probably a network issue.  Does not make sense given 
I can SSH in using another user.

Any thoughts are much appreciated.

Keith