If there is a bike on the dock, it means the bike is broken and cannot be used until it is fixed by a technician. If there is no bike on the dock, it means there is an issue with the dock. It will not accept a bike return. If the bike you take out has an issue, just return it to the closest dock and press the button with the wrench icon. If you have difficulty finding a working dock please reach out to Customer Service through +97144405263 (timings 8 AM - 11 PM) or click here to send us an email for further instructions.