Merge pull request #308 from Molrn/fix-flask-followup-questions-error

fix(flask): no followup questions error

src/vanna/flask/__init__.py

@@ -319,6 +319,7 @@ def generate_followup_questions(id: str, df, question, sql):
                     }
                 )
             else:
+                cache.set(id=id, field="followup_questions", value=[])
                 return jsonify(
                     {
                         "type": "question_list",