If the event occurs to the party and at the time of the incident. The provider was unable to perform the contract. The parties both parties without any liability.
If it is come with the client. And during the time of the incident. Service providers can not perform under the contract. For both parties, without any liability to each other.
If the incident happened with the service recipients. And in time, the scene said. Unable to proceed with the service contract. Let the parties without any liability for each other.