I have a workflow that supports two types of similar activities, in this example Type A and Type B. The first step of the state machine is to add detail to the request which varies by type. Once the information is added the state advances to an approval phase. The approval task is the same for both types A and B. Approvers receive flexi task emails for type A but do not receive emails for type B. Once approved, the state advances and emails are received for both types. What would prevent the flexi task emails for type B? The approval task is identical and does not distinguish between the two types. I have delete the approver flexi task and recreated it from scratch only to have the same issue persist. Ideas?
There is an action called "Log in history list". This is out of the box Nintex workflows. You click on the 'Operations' tab in the workflow design manager and you'll find that action in there. Drag and drop it where you question there is a problem in your workflow. Double click the action and you can write text that you want to appear in the Nintex history. You can also have Nintex variables and columns values appear in the log. Its very customizable. It is a good troubleshooting tool. In the coding world, we use alert boxes and write on the screen and use developer tools. This particular action is very useful when you can't find what's wrong with your workflow. In order to see what's been written to the log, right click the item in your list and select view workflow history. Click on the name of your workflow and then View Details. The log should appear at the bottom of the page.
The only way for the Approval branch to distinguish between A & B is to test for Type A vs Type B as you do under the Add Detail branch. I'm not sure why you don't want a task notification for Type B & I suspect you're setting the task notification delivery type to None, but as burkslm suggested, you need to verify that your actually running through the Type B condition.
As mentioned, aside from the logic issues, you can avoid the email for Type B's task by setting the task notification delivery type to None. I believe the task is still created, but notification is not sent. The Nintex documentation doesn't clarify this.