Shoutout to @0scar for posting a photo of the filament sensor, that was super helpful. Also thanks to everyone else who pointed me to the filament sensor and resources around that.
I also tracked down this review which had great information around my printer's filament sensor as well. It turns out that the hole that goes to the sensor is way too big and there's a lot of play with the filament. As I jiggled the filament up & down I could hear the sensor clicking on & off, clearly indicating that if the angle of entry of the filament was too low, the sensor would not be depressed and this would continue to be a problem.
So for my next print, I did what that reviewer suggested and simply unscrewed the sensor & taped it so it would not stop my print. My print was unsuccessful for other reasons (under-extrusion/failed to adhere to the build plate 😫), but at least I think I've figured out what's going on with my filament sensor. Thanks again everyone!
