Confirmation node hasn't responded after digital form acceptance

i created a dialog box after that add entity node(Mobile_no) then add digital form to book an appointment then add confirmation node to get a answer in form of yes or no and added service node with yes. but when i started running of bot . digital form successfully submitted but after that confirmation node hasn’t activated and task discarded. Please suggest how to resolve asap.
Bot Response:-
NewBooking Form is successfully submitted.
I am sorry, something went wrong and I had to discard your task. Please retry.

It appears the content of your confirm_appt message cannot be executed. Please share the details of the confirm_appt node if you would like assistance. It would also be useful to see the dialog flow around that node.
It is interesting that you still get the “yes” “no” options even though the message text can’t be generated. The same node errors and then completes…very odd behavior.