unique type option in mongoose does not work with graphql-compose-mongoose

[Giayychan]

Noob here. I have the below schema declared however I can still save duplicate email data with mongoose and no errors are thrown. Am I doing something wrong?

userSchema.ts

import { composeMongoose } from 'graphql-compose-mongoose';
import { schemaComposer } from 'graphql-compose';

export interface IUser {
    firebaseUid: string;
    emailVerified: boolean;
    email: string;
}

export interface IUserDocument extends IUser, Document {}

export const UserSchema = new Schema<IUser>({
    emailVerified: { type: Boolean, required: true, default: false },
    firebaseUid: { type: String, required: true, unique: true },
    email: { type: String, required: true, unique: true }
});

export const User = model<IUserDocument>('User', UserSchema);

const customizationOptions = {};

export const UserTC = composeMongoose(User, customizationOptions);

schemaComposer.Query.addFields({
    userById: UserTC.mongooseResolvers.findById(),
    userMany: UserTC.mongooseResolvers.findMany()
});

schemaComposer.Mutation.addFields({
    userCreateOne: UserTC.mongooseResolvers.createOne(),
    userUpdateById: UserTC.mongooseResolvers.updateById(),
    userUpdateMany: UserTC.mongooseResolvers.updateMany(),
    userRemoveById: UserTC.mongooseResolvers.removeById()
});

export const userSchema = schemaComposer.buildSchema();
export default userSchema;

package.json

"devDependencies": {
        "@types/express": "^4.17.14",
        "@types/jest": "^29.1.2",
        "@typescript-eslint/eslint-plugin": "^5.38.1",
        "@typescript-eslint/parser": "^5.38.1",
        "eslint": "^8.24.0",
        "jest": "^29.1.2",
        "nodemon": "^2.0.20",
        "ts-jest": "^29.0.3",
        "ts-node": "^10.9.1",
        "typescript": "^4.8.4"
    },
    "dependencies": {
        "@apollo/server": "^4.0.0-rc.14",
        "body-parser": "^1.20.0",
        "cors": "^2.8.5",
        "dotenv": "^16.0.3",
        "express": "^4.18.1",
        "graphql": "^16.6.0",
        "graphql-compose": "^9.0.9",
        "graphql-compose-mongoose": "^9.7.2",
        "http": "^0.0.1-security",
        "mongoose": "^6.6.3"
    }