eufy 11s making a grinding noise and the rolling brush isn't spinning

The rolling brush is jammed, usually with hair or string. You'll need to remove it and clear the obstruction.

Here's how you do it:

1. Turn the RoboVac over. Find the brush guard on the bottom.
2. Pull on the two release tabs to unlock the brush guard, then lift it open.
3. Lift the rolling brush out of its housing.
4. Use the provided cleaning tool (or scissors carefully) to cut and remove all hair and debris wrapped around the brush ends and along its length. Clean the brush guard area too.
5. Reinstall by inserting the fixed protruding end of the brush into its slot first, then clicking the other end into place.
6. Press down on the brush guard until it snaps securely shut.

If that didn't work: Make sure the brush and guard are installed correctly and fully seated. If the brush still doesn't spin after a restart, there may be a mechanical fault.

Keep it clean: Do this once a week. Replace the rolling brush every 6 to 12 months.