DIAGNOSIS: This is by design—the round shape and side brush placement mean it cannot get into a true 90-degree corner. The 'Edge' mode improves but doesn't eliminate this gap.
FIX: Use BoostIQ or Max suction mode. The stronger suction will pull more debris from corners toward the main brush intake. Also, ensure the side brush is installed and not broken; it's responsible for flicking edge debris into the path.
IF THAT DIDN'T WORK: Your room layout may be confusing its algorithm. Run it in 'Edge' mode from the app for a focused edge-cleaning run. For permanent problem corners, you'll need to do a quick manual pre-sweep.
HEADS UP: The side brush wears out. If the bristles are bent or shortened, replace it. A new brush spins faster and flicks debris more effectively. This is a consumable part, like the filter.