Ubuntu 20.04 Downgrade gnome from 40 to 30s

I installed Gnome 40 to try but I want to return to the last one, maybe 38 or 39

I did this for upgrade

sudo add-apt-repository ppa:devacom/x11 -y
sudo add-apt-repository ppa:devacom/gnome-40 -y
sudo apt install ubuntu-desktop gnome-shell gnome-control-center
sudo apt upgrade

I tried sudo apt install ubuntu-desktop gnome-shell gnome-control-center but return

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 gnome-control-center : Depends: gnome-control-center-data (< 1:3.37) but 1:40.0-1ubuntu4 is to be installed
                        Depends: gnome-settings-daemon (>= 3.29) but it is not going to be installed
 gnome-shell : Depends: evolution-data-server (>= 3.33.1) but it is not going to be installed
               Depends: gir1.2-gweather-3.0 (>= 3.25.91) but it is not going to be installed
               Depends: gnome-settings-daemon (>= 3.16.0) but it is not going to be installed
               Depends: gnome-shell-common (= 3.36.9-0ubuntu0.20.04.2) but 40.5-1ubuntu1 is to be installed
               Recommends: gdm3 (>= 3.10.0.1-3~) but it is not going to be installed
               Recommends: ubuntu-session but it is not going to be installed or
                           gnome-session but it is not going to be installed
 ubuntu-desktop : Depends: gdm3 but it is not going to be installed
                  Depends: gnome-settings-daemon but it is not going to be installed
                  Depends: gnome-shell-extension-ubuntu-dock but it is not going to be installed
                  Depends: ubuntu-desktop-minimal but it is not going to be installed
                  Depends: ubuntu-session but it is not going to be installed
                  Recommends: gnome-calendar but it is not going to be installed
                  Recommends: gnome-initial-setup but it is not going to be installed
                  Recommends: gnome-todo but it is not going to be installed
                  Recommends: network-manager-openvpn-gnome but it is not going to be installed
                  Recommends: yaru-theme-gnome-shell but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

any way for the downgrade?

update:

now after solution suggested gnome does not work at all.

first, it was a black screen, then I change to lightdm with sudo dpkg-reconfigure lightdm, now if at login, from select desktop env choose ubuntu (what I belive its gnome), the apps open, but no wallpaper (with ops ...., logout) and apps windows without x or maximize buttons, basically it's broken

You have to use ppa-purge utility for this purpose as follows:

sudo apt-get update
sudo apt-get install ppa-purge
sudo ppa-purge ppa:devacom/gnome-40
sudo ppa-purge ppa:devacom/x11

then reinstall ubuntu-desktop task-package and others by

sudo apt-get install --reinstall ubuntu-desktop^ gnome-shell gnome-control-center
sudo apt-get upgrade

Before proceeding, make sure you have got a backup of /home (or anything important) and create a bootable media (in case something goes wrong, you can reinstall the OS using the bootable media; and restore the important data from backups).

1. Create a file called focal.pref in /etc/apt/preferences.d/ using the touch command:

   sudo touch /etc/apt/preferences.d/focal.pref
   

2. Edit the file using a text editor (example: sudo -H gedit /etc/apt/preferences.d/focal.pref) and copy-paste the following lines into it:

   Package: *
   Pin: release v=20.04, a=focal-security
   Pin-Priority:1001
   
   Package: *
   Pin: release v=20.04,a=focal-updates
   Pin-Priority: 1001
   
   Package: *
   Pin: release v=20.04,o=Ubuntu,a=focal
   Pin-Priority: 1001
   
   Package: *
   Pin: release v=20.04,o=Canonical,a=focal,n=focal,c=partner 
   Pin-Priority: 1001
   

3. Update and upgrade your system. Since this can be destructive if there are breaks and conflicts in packages, use the --dry-run argument to simulate the upgrade:

   sudo apt-get update && sudo apt-get --dry-run dist-upgrade
   

   Look for any conflicts. If you are unsure about conflicts, edit your question and paste the output of the commands onto it. After you are sure that there are no conflicts or breaks, run an upgrade (dist-upgrade):

   sudo apt-get dist-upgrade
   

This is an attempt to revert your installed packages to the default version of the packages (the ones which are available in the repositories).

N.B: The above can be dangerous, especially if other foreign sources or focal-backports are enabled on your system.

To get a brief idea of what we did above, see: What is Pinning?.