You have a frozen supply pipe then, probably. It's often a problem with the tap in the street. If you know which is your tap in the road, usually in the path at your entrance, then flip up the cover, remove the foam plug and pour warm water down onto the tap. It may take some time. When you replace the foam plug make sure that it is a snug fit across the access pipe - most of them are just stuffed in the hole with no thought...
It's not impossible that the freeze is in the house, especially if the pipe comes up against an outside wall, usually under the sink.
No guarantees with any of this..