Preferably the number for the specific contact name if added.
If there is a specific telephone number to contact for the service then include those details.
If an telephone number has been listed for the organisation then this will be brought through automatically, but should be changed if there is a specific contact number for the service.
If the telephone number brought through from the organisation details is not a personal one then this can be left if you are not able to replace it.
However, if it is unlikely that the telephone number listed in the organisation information would be the one where support about the service could be found then these numbers should be removed even if you can't include any other details.
Please ensure this information is for people who would expect to respond to calls about the service - it will create a poor experience where people contact and are told, it is the wrong number.