It is possible to remove the water level observer, as well as watching it submerged in the water tank.
1. Check whether the bottom buoyancy sponge is still there, if not, replace the water level marker.
2. If the buoyancy sponge is still there, please use your finger to check whether it can move. If it cannot move, the float may be stuck. Replace the water level marker.
3. If it can be moved, please insert it back into the water inlet to confirm.