DIAGNOSIS: This is the G30's cliff sensor being triggered by dark-colored or high-pile rugs. The vacuum thinks it's at a staircase edge and panics, aborting the docking sequence.
FIX: Cover the cliff sensors with transparent tape. The two infrared sensors are on the underside, near the front caster wheel. Use clear packing tape or similar. This blocks the false signal from the rug.
IF THAT DIDN'T WORK: The issue might be the charging contacts on the dock or the robot. Clean both with a dry cloth. If they're corroded, use a pencil eraser gently.
HEADS UP: With sensors taped, never run the vacuum near actual stairs. You'll need to manually create a virtual boundary or use no-go strips in the app for real drop-offs.