"TypeError: 'NoneType' object is not iterable" error comes when form submit execution

Following error come when form class execute submit function.

[2019-08-03 12:37:24,493] ERROR in app: Exception on /webhook [POST] Traceback (most recent call last): File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 2292, in wsgi_app response = self.full_dispatch_request() File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 1815, in full_dispatch_request rv = self.handle_user_exception(e) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask_cors/extension.py”, line 161, in wrapped_function return cors_after_request(app.make_response(f(*args, **kwargs))) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 1718, in handle_user_exception reraise(exc_type, exc_value, tb) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/_compat.py”, line 35, in reraise raise value File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 1813, in full_dispatch_request rv = self.dispatch_request() File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 1799, in dispatch_request return self.view_functionsrule.endpoint File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask_cors/decorator.py”, line 128, in wrapped_function resp = make_response(f(*args, **kwargs)) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/rasa_core_sdk/endpoint.py”, line 86, in webhook response = executor.run(action_call) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/rasa_core_sdk/executor.py”, line 177, in run events = action(dispatcher, tracker, domain) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/rasa_core_sdk/forms.py”, line 411, in run events.extend(self.submit(dispatcher, temp_tracker, domain)) TypeError: ‘NoneType’ object is not iterable 2019-08-03 12:37:24 ERROR flask.app - Exception on /webhook [POST] Traceback (most recent call last): File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 2292, in wsgi_app response = self.full_dispatch_request() File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 1815, in full_dispatch_request rv = self.handle_user_exception(e) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask_cors/extension.py”, line 161, in wrapped_function return cors_after_request(app.make_response(f(*args, **kwargs))) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 1718, in handle_user_exception reraise(exc_type, exc_value, tb) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/_compat.py”, line 35, in reraise raise value File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 1813, in full_dispatch_request rv = self.dispatch_request() File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask/app.py”, line 1799, in dispatch_request return self.view_functionsrule.endpoint File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/flask_cors/decorator.py”, line 128, in wrapped_function resp = make_response(f(*args, **kwargs)) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/rasa_core_sdk/endpoint.py”, line 86, in webhook response = executor.run(action_call) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/rasa_core_sdk/executor.py”, line 177, in run events = action(dispatcher, tracker, domain) File “/home/aarbor_01/anaconda3/lib/python3.6/site-packages/rasa_core_sdk/forms.py”, line 411, in run events.extend(self.submit(dispatcher, temp_tracker, domain)) TypeError: ‘NoneType’ object is not iterable

I’m using rasa-nlu=0.14.6, rasa-core=0.13.6 versions.

Hi @Prakash_Raj! Can you please share the story for this form?