how to move subtask under issue type for next sprint

[Garden16]

To manage defects, we use defect subtasks under the bug issue type. For a specific sprint, defects (defect subtasks) are opened under Bug issue. Any open defect subtasks (defects) that do not have resolutions and are not in status closed must be moved to the bug issue type for the next sprint.

How do I transfer open defect subtasks from Sprint 1 to Sprint 2? It is possible to create an automated rule that moves all defect subtasks that are not closed to the bug issue type for the second sprint.

[Nic Brough -Adaptavist-]

You do not.

Sub-tasks are not sprint items, they don't go into sprints themselves. 

They can be thought of as being in a sprint only when the issue that they are a part of is in the sprint.

What you are doing is not good practice and it certainly is not Scrum or Agile.  It sounds like you should be raising bugs as sprint items (stories) and putting them in the backlog as usual.

[Garden16]

They can be thought of as being in a sprint only when the issue that they are a part of is in the sprint. 

Here in this scenario, the bug issue type belongs to a certain sprint 

How do I transfer open defect subtasks from Sprint 1 to Sprint 2? It is possible to create an automated rule that moves all defect subtasks that are not closed to the bug issue type for the second sprint.

1: Sprint 1 -> Bug issue type -> 1: Defects subtasks - status - Closed  

                                                   2: Defects subtasks one - Status - Open

2: Sprint 2 -> Bug issue type-> Add  the Open status Defect subtasks from sprint 1 under sprint 2 Bug issue type

I need an  automated flow to transfer the open status defect subtasks to move under the next sprint's bug issue type

[Nic Brough -Adaptavist-]

Again, you do not transfer sub-tasks between sprints.  Sub-tasks are not sprint items, they're only in a sprint because their parent is - they are a part of their parent story.

The parent story is not done if it has open sub-tasks, and when that moves into the next sprint (because it is not done) all the bits of it move with it.

Quite simply, you do not need to automate anything here, Jira handles it all for you, off-the-shelf.