SSH not working Raspberry Pi4

Hi All.
I bought a Raspberry Pi4.
Downloaded image Raspberry Pi 64-bit 20.04.1.
I wrote the image to a USB flash drive, created a file SSH with no extension to include SSH on boot.
Error while connecting: "ssh: connect to host 192.168.6.146 port 22: Connection refused".
If install the usual Ubuntu 20.04, no problem, SSH is working.

I just installed ubuntu-mate-20.04.1-beta2-desktop-armhf+raspi.img.xz image for the Pi4B, I don't think ssh server is included by default.

I did most of my setup and configuration over ssh after the initial boot with attached KVM and sudo apt install ssh (and a few other things like samba).

Same problem , not able to connect via SSH.
: Connection refused".

I seem to have used 2 different routes to fix this on different installs:

  1. sudo apt install openssh-server
  2. from the software boutique under servers
    HTH
    Derek