DIAGNOSIS Its navigation is confused because it's working in low light or an overly cluttered/open space. The 694 uses a bump-and-go method, not mapping.
FIX Turn on more lights in the room before starting a clean. This robot needs decent ambient light for its basic optical sensors to orient itself. A dark room makes it act drunk.
IF THAT DIDN'T WORK Check for and clean the front bumper sensor window (the small, dark plastic strip above the bumper). A smudge there can mess with its perception. Wipe it with a dry microfiber cloth.
HEADS UP This model is designed for multiple passes over an area. It will eventually cover the room, but it's not efficient. For better coverage, run it more frequently so it starts from different spots.