If you are not able to get to customer's home, we recommend contacting the customer (their contacts are available from the job details page).
If you don’t hear from them immediately please contact with support immediately, and  wait 15-20 minutes after the booking start time, before leaving and checking out. Try contacting your customer a few more times. If you haven't heard from your customer at the end of 20 minutes, feel free to go. Remember to alert Done when you have issues completing a job.