That error is, I think, coincidental. It is alerting you that one of the repositories cannot be reached due to network error.
I am going to crosslink this here:
This marks the third thread I have seen so far mentioning this.
I think we might try alerting the ZorinGroup to this issue.
In the meantime, in terminal can you run
rm -rf /var/lib/apt/lists/*
sudo apt clean && sudo apt autoclean && sudo apt autoremove
sudo apt update && sudo apt upgrade