Your cutting height is uneven or you're mowing too fast. Here's the fix, in order of likelihood:
- Check all four wheels. The height adjustment levers on each wheel must be set to the same position. One wheel being higher will tilt the deck.
- Slow your pace. This mower has a Smart Pace system, but pushing too fast still causes missed cuts, especially in thick grass.
- Inspect the deck. Remove the battery and tip the mower. Check for grass clumps stuck underneath that disrupt airflow.
If that didn't work: The blade might be damaged or installed upside down. A bent blade won't cut cleanly. Replace it with a Greenworks replacement blade.
Heads up: For a cleaner cut, never remove more than one-third of the grass blade height in a single mowing.