app/views/admin/sessions/_otp_form.html.erb
<h2>
Two-factor authentication
</h2>
<p>
Enter a one-time code from your authenticator app to proceed.
</p>
<div class="field">
<label for="otp">6 digit code</label>
<%= text_field_tag(:otp, "",
autofocus: true,
autocomplete: "one-time-code",
size: 6) %>
</div>