When the satellite signal reception is great (the mower displays a solid blue light), VisionFence will be automatically disabled during edge cutting or planned cuts near the boundary.
The logic of VisionFence being disabled is to achieve an ideal edge-cutting result. Since if VisionFence is functioning during edge cutting, it may detect real boundaries as obstacles and guide the mower to move away from them. Therefore, causing some grass on the boundary remains uncut.
If the collision is on a boundary, you may have drawn the mower too close to the boundary when creating the map boundary.
If the map is too close to the boundary, even if the positioning signal is good, the positioning may deviate within 20 cm, so it might hit an obstacle on the edge. To solve this problem, you can slightly adjust the boundary. Go to Setting - Map management - Edit map.
If the collision is not on the boundary, please refer to the article below for possible solutions: