If, for whatever reason, you need to have an action re-fire to send the email again or post data, you can easily do that!
Go to the Results > Individual Responses. Click a response and then click the Action Log. You'll see a list of the actions in your project and a button to re-fire that action.
Note: If you have Logic rules applied to your action the re-fire will adhere to these same conditions. As such, if the logic has not been met, the Re-fire action will not bypass the logic in order to fire the action.
The following actions can be re-fired: