The hexagon socket screws securing the handle assembly have likely loosened.
- You'll need a hex key. Locate the four hexagon socket screws (part number 5620161005) where the handle attaches to the beam assembly.
- Tighten each one firmly. Check the four prevailing torque hexagon nuts (part number 5630006002) on the opposite side as well.
- Also check the clamp (part number 3126763001) and clamp block (part number 3126761001) on the lower handle. Tighten any loose screws there.
If that didn't work, inspect the rubber block (part number 3126832001). If it's worn or missing, it will cause play. Replace it.
Heads up: Check these fasteners at the start of each mowing season. Vibration from mowing can work them loose over time.