Checkbox Validation

Hello I get this error TypeError: b is undefined when I add:

class="required" to checkbox.

<div class="col_full">
<div class="form-check">
<input class="form-check-input required" type="checkbox" id="privacyCheck">
<label class="form-check-label" for="privacyCheck">Privacy Policy</label>
</div>
</div>

<div class="col_full">
<div class="form-check">
<input class="form-check-input required" type="checkbox" id="termsCheck">
<label class="form-check-label" for="termsCheck">Terms and conditions</label>
</div>
</div>

How to solve?

Never mind it requires a name attribute.