After Drupal 7.67 and CiviCRM 5.18.4 upgrades, when you click on add a case, the correct screen opens, you can enter data, then save, and the number of cases showing in the constituent summary is incremented, but no new cases show up in a list to be managed. This was previously, for several years on prior versions, working correctly, Also, even for existing cases, the activity dropdown list is not being populated, although they have worked in the past and the Activity Type Options are correctly setup.
So now, in short, the number of cases in the Contact Summary is correct, such as 2 for a certain client, but when you click on the Cases tab, only 1 case appears. CiviCRM was no upgraded to 5.19.0 and the problem persists.
Examining the Case data directly in the database shows no clear reason for this. Furthermore the options for activity_type for the CiviCase component are also in the database and match those of a fresh install.
Has anyone run into this or can you suggest other things I can do to troubleshoot?