Possible Causes and solutions:
1.The washer is too much higher than the water surface level.
It is suggested to lower the washer, and make sure the distance.
2.The hose female connector connector are poorly and the hose male connected.
It is suggested to connect the hose female connector to the hose male connector properly.
3.The water inlet filter is blocked or not fully submerged in water.
It is suggested to clean the water inlet filter/filter head and fully submerge them in water.
4.The hose is bent or twisted.
It is suggested to straighten the hose.