fix some collection issues

atlas/models.py

@@ -1028,6 +1028,12 @@ class SeriesDetail(models.Model):
 
 
 class CaseDetail(models.Model):
+    """A through table that stores the relationship between a case and a collection.
+
+    This is what user answers are linked to (as there be different questions for the same case in a different collection)
+
+    The collection questions and answers are also defined here.
+    """
     case = models.ForeignKey(Case, on_delete=models.CASCADE)
     collection = models.ForeignKey(CaseCollection, on_delete=models.CASCADE)
 
@@ -1109,8 +1115,15 @@ class BaseReportAnswer(models.Model):
         for name, value in self.question.question_schema["properties"].items():
             print(name, value)
 
-            user_answer = self.json_answer[name]
-            correct_answer = self.question.question_answers[name]
+            try: 
+                user_answer = self.json_answer[name]
+            except KeyError: # If the schema has changed?
+                user_answer = ""
+            try: 
+                correct_answer = self.question.question_answers[name]
+            except KeyError: # If the schema has changed?
+                correct_answer = ""
+
             print(correct_answer)
 
             match value: