Fee Payment and Booking an Appointment

I am on H1B and my wife is on H4.
We are planning to go for a Visa stamping at US Embassy in New Delhi
I filled my DS 160 and for my wife as a family application.
Now when I go to the payment site at usvisascheduling.com, it asks My DS 160 number and an amount of 205 USD.
I am not sure if that is correct as I want to book the same date for both me and my wife and expect it to charge me 410 USD.

VAC team responded by saying that you can do that under manage dependents.
There you can add them if wanted to apply together.
I already see my wife name as dependent.
When I go to the payments page, it still says the number of applicants as ‘one’

It is all very confusing.

Please help.