An error while changing text with javascript

I’m using google recaptcha with my django project. But it is not English. So I want to change its writing with javascript.

html

{% extends 'base.html' %}
{% block content %}
<div class="form-body">
    <div class="row">
        <div class="form-holder">
            <div class="form-content">
                <div class="form-items">
                    <h1>Registration</h1>
                    <br><br>
                    <form class="requires-validation" method="POST" novalidate>

                      {% csrf_token %}
                      {{form.as_p}}
                        <div class="form-button">
                            <button id="submit" type="submit" class="btn btn-primary">Register</button>
                        </div>
                    </form>
                </div>
            </div>
        </div>
    </div>
</div>

<script type="text/javascript">
  document.querySelector('recaptcha-anchor-label').innerHTML = "I'm not a robot";

</script>

{% endblock %}

After I did that it won’t apply the html in browser. Below the error message:

Cannot set properties of null (setting ‘innerHTML’)