Waistcoat sleevesless pure wool with ZIP

The jacket it is so good, but too big for me and I am trying to change back sending an email to know how to do it, but anyone responded to me. I dont know how to change my size for extra small one. I dont know how the costumer support is so bad
Esprit Nordique Sorry for the time of answering, with covid and sanitary measures, we are overbooked.
Thanks for your understanding.