In order to sync Sub-tasks, you need to make sure you to sync the parent task first. So if you sync subtasks before the parent task, you will get an error. Then, the way you have the mapping is fine, the problem here is that you are trying to sync a sub-task and the parent ID information is missing, therefore it throws this error as an “Issue type” error. However, this should not be a problem:
//The connection name in this example is heidix_to_cinetix-group.
3. Make sure to save and publish changes. Make sure to sync the parent task first and then try sub-tasks.
Let me know if this works for you.
Kind regards,
Ariel