metatags don't show for custom content type with existing metatags

ok, i just did a bit more debugging:

1. started a new site (test) with our 3 custom content types and no Metatag nor this module
2. installed this module (which brought in the Metatag module)
3. enabled the same modules as my previous site (named schemaorg-metadata)
4. went to create new default metatags for 1 of our custom content types (event) and the additional metatags from this modules show up (see attached works.png)

also i want to show what happens in my original schemaorg-metadata site for the same event content type which had existing metatags and i deleted the entire content type so i can try again, when i initially go to /admin/config/search/metatag/add, i see the listing of of metatags which includes the additional ones provided by this module (see before.png) but then when i select the Event type, the additional metatags options disappear (see after.png)! So it seems the data in the database wasn't cleared; is there a way to clear the metatags for an existing content type so i can start over setting the metatags?