How do I change/update a candidate's personal details as a provider?

You can only update personal details if the employee/candidate has not completed their 
questionnaire. If the person has not completed their questionnaire, then you can notify the 
client to edit these details.

Once the person completes their questionnaire the information is stored and 
cannot be changed.

If the questionnaire is complete, The booking request would need to be cancelled and a new request would need to be submitted with the correct details.