Task-oriented dialogue about: taxi

I am wanting to book a taxi. I am going to Sitar Tandoori and want to leave after 19:30.
Ok, what is your destination?
i'm going to sitar tandoori.
I'm sorry. I meant to ask where are you departing from?
I am departing from la tasca.
I've booked a grey BMW, the contact number is 07618837066.
Thanks so much for your help
Thank you goodbye