1. First, open the toilet's water tank and check the position of the inner scoop when the water tank is full. If the scoop is at a certain level when the tank is full, and the tank is still filling, it will definitely leak.

Two. Use your hand to pull the lever of the drainage scoop, and check the sensitivity of the scoop. If it feels stiff or difficult to move, it indicates that the scoop device is malfunctioning. Remember to press the scoop slightly; do not press it too high.
Three. Remove the water scoop device, then clean it thoroughly. If it is difficult to remove, try placing dry water directly into the water tank and cleaning with dish soap or laundry detergent. If it no longer leaks, you can continue to use it. If not, it needs to be replaced.
Four. If the internal equipment is functioning correctly, inspect the exterior of the tank to check the position of the stainless steel pipe connection and ensure that it is properly tightened or that the internal gasket has deteriorated, causing leaks.
Five. If the water tank is severely damaged by external impact, it may also cause cracking and leakage. The water tank can be replaced, or it can be re-sealed with waterproof adhesive.