Hi! Sorry for mistake in documentation.
Please use addClient method of public service or signUpClient method of public service.
It will return client object.
As i mentioned before - addClient or signUpClient of public service will return client object with client hash.
Can you give an example of how I can use the book() method of the client service? Specifically, what do I need to specify for the clientData?
In case you are using Client Login custom feature then you need to pass client_id and client_sign to clientData.
In case you are not using Client Login then you need to pass name, phone and email.