[Django]-ModelForm and ModelSelect2Widget (django-select2)

Did you follow all the steps in the getting started section?

1. Add django_select2 to your INSTALLED_APPS in your project settings.

2. Add django_select to your urlconf if you use any ModelWidgets:

   url(r'^select2/', include('django_select2.urls')),
   

3. Add the CSS to the head of your Django template:

   {{ form.media.css }} 
   

4. Add the JavaScript to the end of the body of your Django template:

   {{ form.media.js }}
   

Also, there appears to be an external dependency not provided by the module itself:

External Dependencies

jQuery version 2 This is not included in the
package since it is expected that in most scenarios this would already
be available.

Well, it happens to me too recently… And turns out that the jquery script

(<script src="https://code.jquery.com/jquery-3.5.1.min.js"></script>)

should be placed first before any scripts that use jquery (it will use jquery, but the jquery hasn’t been called).