mapTo object schema property does not work

Hello. I am using the ReactNative SDK and my schema in code looks like this

{
		name: "User",
		primaryKey: "_id",
		properties: {
			_id: "string",
			stytchOD: { type: "string", mapTo: "stytchID" },
			application_id: { type: "string?", mapTo: "applicationID" },
			customer_id: { type: "string?", mapTo: "customerID" },
			first_name: { type: "string?", mapTo: "firstName" },
			last_name: { type: "string?", mapTo: "lastName" },
			dob: "string?",
			address: "string?",
			phone: "string?",
			email: "string?",
			nationality: "string",
			unique_verification_number: {
				type: "string?",
				mapTo: "uniqueVerificationNumber",
			},
			verification_type: { type: "string?", mapTo: "verificationType" },
			photo: "data?",
			isActive: { type: "bool", default: false },
			createdAt: { type: "date", default: new Date() },
			groups: "string[]", //"Group{}"
		},
	}```

But when I console.log the user:

const  user = useObject(User, user.id)
console.log(user)

It looks like this:

{
  "_id": "realm-id-382903289302",
  "address": null,
  "application_id": null,
  "createdAt": 2022-06-27T13:28:52.512Z,
  "customer_id": null,
  "dob": null,
  "email": null,
  "firstName": "miasohoa",
  "first_name": null,
  "groups": Array [],
  "isActive": true,
  "last_name": null,
  "nationality": "AU",
  "phone": null,
  "photo": null,
  "stytch_id": "random-id-37862873892",
  "unique_verification_number": null,
  "verification_type": null,
}

So when I update user.firstName it does not save because the user variable only has a user.first_name property that I cannot access. Am I using the mapTo property incorrectly? I am using a JS class that has instance variables that match the mappedTo names.