Attempting to upgrade Zorin 16.2 to 17.3 but get "Sorry, an internal error happened. The upgrader couldn't complete checking the upgrade requirements". The report reads as follows:
[CHECKING] Started
[CHECKING:Validating Upgrade Attempt] Started
[CHECKING:Validating Upgrade Attempt] Completed
[CHECKING:Checking Filesystem] Started
[CHECKING:Checking Filesystem] Completed
[CHECKING:Creating Necessary Files] Started
[CHECKING:Creating Necessary Files] Completed
[CHECKING:Adding GPG Keys] Started
[CHECKING:Adding GPG Keys] Completed
[CHECKING:Restarting Apt] Started
[CHECKING:Restarting Apt] Completed
[CHECKING:Simulating Flatpak Transaction] Started
[CHECKING:Simulating Flatpak Transaction] Completed
[CHECKING:Processing Apt Repos] Started
[CHECKING:Processing Apt Repos] Completed
[CHECKING:Updating Apt Repos] Started
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Retrying
[CHECKING:Updating Apt Repos] Fatal Error: { error-repo-download-failed: }
[CHECKING:Updating Apt Repos] Failed
[CHECKING] Failed
[CHECKING:Restoring System] Started
[CHECKING:Restoring System] Error: { error-repo-download-failed: }
[CHECKING:Restoring System] Completed
Could anyone help please?