You have an older washer. By now the agitator dogs are loose and broken. Most people will never notice this problem because everything appears normal. Agitator dogs will go out at least once in the lifespan of the washer. The agitator has two parts. The top and bottom. The top half turns in one direction only to pull clothes down from the center. The bottom half agitate back-and-forth to scrub clothes. When “the dogs” go bad, the top half of the agitator will not lock in place to move in one direction only. If you can stop the agitator by hand while clothes are being washed, you have bad dog agitators. They cost $5-$7 for a set of 4 and relatively easy to install in a whirlpool washer. Kenmore washers are more complex.