After the new upgrade of zorin os, When zorin os 16.2 was downloaded to the 16.3 core version, many issues still persisted when software updates were coming, when I installed it with a highspeed broadband internet connection there failed to download packages and no apps downloaded from GNOME software and no apps are updating in the gnome-software. Internet speed is fluctuating too much after the upgrade to 16.3, in 16.2 core it was ok. Why so many issues are there in 16.3
The error you show an image of is caused by a Regional Server not containing all of the proper packages.
And this would make sense in your description of your other issues.
Please launch Software & Updates app. Under "Download from" change the drop down menu option to Main Server.
Close Software & Updates and say yes to the prompt asking to refresh.
Next, open a terminal and run:
sudo apt clean && sudo apt autoclean
sudo apt update && sudo apt full-upgrade
sudo dpkg --configure -a
Reboot and test...
Uncheck the option for Source Code
Everything else looks good in the terminal.
Once Source Code is unchecked, re-run the sudo apt update command.
Launch Software & Updates and then refresh it with close again and see if that error is still there.
You can try
sudo apt update --fix-missing
I see a 404 error there on a server that should be up.
I just ran a test on sudo apt update in my region and no issues - So we must assume there is a failed connection in route, rather than in server. You may have to wait a bit and try again later...
In the meantime, can you please run
sudo apt install xdg-desktop-portal
in order to handle that package being held back.
In this one, uncheck Canonical Partners Source Code.
You can check the option for Canonical Partners.
I may be slow to reply - it is very late (Or early...) here and I need some rest.
Now what to do
rm -rf /var/lib/apt/lists/*
sudo apt clean && sudo apt autoclean && sudo apt autoremove
sudo apt update && sudo apt upgrade
Let's see if it works.
Otherwise, you may need to try again at a later time (potentially less net traffic).
Then also it is not working, I have checked my internet connection using a broadband connection and by using mobile data also.
The pop-up comes 9 times per day and I always keep software up to date
Did you try the things suggested in the two Error messages at the bottom of the last page of your screenshots?
Crosslink:
By your last screenshot, did the remote repository manage to connect?
Yes software updates has updated and it is working fine now but it is getting problem in GNOME SOFTWARE
What is the problem in Gnome Software?
Apps are not updating in strong internet connection