After accepting the calculation error, the device tries to recalculate and comes back with the same error. After acknowledging there are no routable roads, the device should not try to recalculate. I accepted the prompt countless times and 10 seconds later, it would come back. I can see the line of where I want to go in a quarter of the screen while the alert is visible. I'm fine if the route cannot be calculated and I don't care that it does not show me additional roads, but I should be able to at least follow the line and figure out the turn by turn navigation myself.
This issue nearly caused me to be stranded in the middle of nowhere. I had sync'd the route from Strava. I had it pulled up on my phone, but forgot to download the route. Fearing my phone would die from spotty coverage, I put it in airplane mode and did not start the route on the mobile app. I would periodically pull out my phone and see myself moving along the route until the app closed and would not reload since I did not have it offline. That's when I had to resort to following the route on my Garmin with only being able to see the map in a quarter of the screen. I'd have to stop the course anytime I wanted to see any other screen on my device.
I believe the only thing it is trying to "calculate" is the virtual partner, which isn't even a feature I want. The main feature I wanted was to not get lost in the middle of nowhere with no cell service.
From what I read, I would have had to sync my device with Garmin Express on my laptop, but I did not have my laptop with me when I started my route.