I have read many posts but none can be good for me.

my database:

services

-Nw9TVp-6EjCI-xXWO3r
category: "veterinarian"
name: "Center jkhkjhkjh"

--Nw9UmVy3RgDb_wMeVBi
category: "groomer"
name: "Center jkhkjhkjh"

my query is this but the data doesn’t come out:

let rootRef = Database.database().reference()
let ref = rootRef.child("services").child("$servicesId").queryEqual(toValue: "groomer", childKey: "category")

how do I get the value of “category” and the node id?