What is the exact model number of your device, as seen in About Phone, Software Information?
What country are you in?
Your device should be running One UI V5.0.
Do you have a solid WiFi, or Cellular Data connection?
You can try going to Settings > Apps Toggle ON "Show System Apps" middle right click on "OK" and Search for Software Update.
There should be two of these System Apps. Click on each one & Scroll down to "Storage" Clear BOTH Cache & Data for each & Reboot.
Go to Settings > Software Update & check to see if you can Download the update now.
If you still can't, Download & install Smart Switch on both your phone & computer > Connect your phone to your computer & in Preferences in Smart Switch on your computer, I think it's Download updates & see if you can get your phone updated using Smart Switch.
If it still fails, you can try a Factory Reset, but you may need to visit a Samsung Service Centre to get it checked out by a tech.
This is pretty strange all things being equal.
I know that you said you already tried a Factory Reset & Smart Switch, but last resort is visiting a service center, so worth trying again.
You could also contact your Carrier, Telus and ask them if there's a reason why you can't update your device.
From Settings > Apps the two Software Update System Apps?
I'm not talking about Wiping Cache & Data from Recovery.
Seriously the guy at the Samsung Service Centre didn't know what to do?
You could download the Firmware to your computer using Frija & Manually Flash it with Odin, but the Service Centre should absolutely know how to do that..
Also, if you go to Settings > About Phone > Status Information can you post a screen shot of this?
Hi, we appreciate your efforts in performing the necessary troubleshooting steps.
As the issue is still not resolved, we kindly request you to try submitting an error report through the Samsung Members app.
Attaching a log file will help greatly in analyzing the cause of the issue.
We will send a response through Samsung Members.
Tap and hold on Samsung Members Icon and tap on Error report >> select the category from the below >> Describe the issue and check the option "send system log data" then send.