Check alignment, contacts and dock power first.
Roborock’s charging troubleshooting starts with correct contact alignment, clean charging contacts, a firmly connected dock cable and a working outlet.

Find why charging will not start
Does the dock have power when the robot is away?
Check the dock indicator and power connection.
Try these fixes in order
Reseat the robot
Place it squarely on the dock and confirm stable contact.
Clean charging contacts
Wipe the dock and robot contacts; do not work on a powered dock with wet hands.
Check dock power
Firmly connect the cable and test another outlet.
Power-cycle the dock
Disconnect it for about two minutes, reconnect and test once.
When to stop DIY
If a powered dock detects the robot and clean contacts are aligned but charging still fails, do not open the powered dock or battery enclosure. Use qualified service.