Change Ticket Status (Desk) when somebody booked a Service (Bookings) with Flow

Change Ticket Status (Desk) when somebody booked a Service (Bookings) with Flow

Hi,

Im using Zoho Desk as a ticketsystem where i change the status manually to "Invite", to sent a link to my Service i created in Zoho Bookings, where people can book my service on their own. This works perfect except, that i don't get a feedback in Desk, whenever my client booked it. (i only get an confirmation email)

Now i want the status of the corresponded ticket to be changed to "Booked", so i know (and see in Desk) that the ticketrequester did follow up my invitation. 

Im not sure how to achieve this and i have at least 2 options.

1. Directly create a flow to act whith the trigger Appointment booked or 
2. Create a flow based upon the confirmation e-mail i get in my e-mailbox.

I wish there was already a native-build-in solution in Desk for this. I would like to see in a ticket, a date when my service is booked, so i know my client already booked it and when. But until then i need to create a workaround for it.

Without this feature, i have to manually check my tickets and compare them to the calender, and i want to sent reminders to book my service, when my client didnt book it.

Anyone has an example on howto create a flow to change the status of a ticket?