Creating plugin for Django-CMS

Creating plugin for Django-CMS

I think I screwed up somewhere while trying to create a django-cms plugin
and now I am unable to go back. The plugin (called sbbplugin) seems to be
"working" (it gets displayed) but whenever I try to publish the site I get
the following error:
DatabaseError at /admin/cms/page/18/publish/
relation "cmsplugin_sbbmodel" does not exist
LINE 1: ...id", "cmsplugin_sbbmodel"."cmsplugin_ptr_id" FROM "cmsplugin...
^
I tried removing the plugin but I can not do it because the page is not
published. My plugin has no models or anything. Also I'm unable to remove
the plugin from the page by clicking delete. Seems like the database is
broken. Since I am not experienced enough to know what information you
need I would appreciate it, if you could give me further instructions on
what I should do. I really don't want to loose the database and start over
again.
P.S. I just tried to follow these instructions:
http://docs.django-cms.org/en/2.4.2/extending_cms/custom_plugins.html (
the simplest one)