User Meta Fields not saving on registration

Hi,

I added two fields to the register form (first name and last name) but those won’t save in the database at all.

The files I have worked on :
– masterstudy-lms-learning-management-system/assets/js/register.js
– masterstudy-lms-learning-management-system/stm-lms-templates/account/register.php

The changes I made :

In the PHP file :

<div class="row">
            <div class="col-md-6">
                <div class="form-group">
                    <label class="heading_font"><?php esc_html_e('First Name', 'masterstudy-lms-learning-management-system'); ?></label>
                    <input class="form-control"
                           type="text"
                           name="first_name"
                           v-model="first_name"
                           placeholder="<?php esc_html_e('Enter first name', 'masterstudy-lms-learning-management-system'); ?>"/>
                </div>

            </div>
            <div class="col-md-6">
                <div class="form-group">
                    <label class="heading_font"><?php esc_html_e('Last name', 'masterstudy-lms-learning-management-system'); ?></label>
                    <input class="form-control"
                           type="text"
                           name="last_name"
                           v-model="last_name"
                           placeholder="<?php esc_html_e('Enter your last name', 'masterstudy-lms-learning-management-system'); ?>"/>
                </div>
            </div>
        </div>

In the JS file :

function stm_lms_register(redirect) {
  var vue_obj = {
    el: '#stm-lms-register',
    data: function data() {
      return {
        vue_loaded: true,
        loading: false,
        login: '',
        email: '',
		first_name: '',
		last_name: '',
        password: '',
        password_re: '',
        message: '',
        status: '',
        site_key: '',
        become_instructor: '',
        degree: '',
        expertize: '',
        recaptcha: '',
        captcha_error: '',
        privacy_policy: true,
        has_privacy_policy: false,
        choose_auditory: false,
        auditory: ''
      };
    },
    methods: {
      hasPrivacyPolicy: function hasPrivacyPolicy() {
        if (!this.has_privacy_policy) {
          this.has_privacy_policy = true;
          this.privacy_policy = false;
        }
      },
      register: function register() {
        var vm = this;
        vm.loading = true;
        vm.message = '';
        var data = {
          'user_login': vm.login,
          'user_email': vm.email,
		  'first_name': vm.first_name,
		  'last_name': vm.last_name,
          'user_password': vm.password,
          'user_password_re': vm.password_re,
          'become_instructor': vm.become_instructor,
          'privacy_policy': vm.privacy_policy,
          'degree': vm.degree,
          'expertize': vm.expertize,
          'auditory': vm.auditory
        };

        if (vm.site_key) {
          grecaptcha.ready(function () {
            grecaptcha.execute(vm.site_key, {
              action: 'register'
            }).then(function (token) {
              data['recaptcha'] = token;
              vm.processRegister(data);
            });
          });
        } else {
          vm.processRegister(data);
        }
      },
      processRegister: function processRegister(data) {
        var vm = this;
        vm.$http.post(stm_lms_ajaxurl + '?action=stm_lms_register&nonce=' + stm_lms_nonces['stm_lms_register'], data).then(function (response) {
          vm.message = response.body['message'];
          vm.status = response.body['status'];
          vm.loading = false;

          if (response.body['user_page']) {
            if (redirect) {
              window.location = response.body['user_page'];
            } else {
              location.reload();
            }
          }
        });
      },
    }
  };
  new Vue(vue_obj);
}

I successfully modified the basic WP registration form (by creating another plugin that only works with PHP and Ajax), but I want to do those changes on the MasterStudy LMS registration form. How can I achieve that ?

Thank you very much for your help !

Cheers,
Adelythe

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