Getting an Approval error.

I have created the scope change work item type with all the presentation and attributes set. Now when try to create Scope change work item it gets saved successfully in new state now when try to take that work item to another state In Analysis I am not able to save that work item. It shows the error "Required Approval of Type 'Approval' is not present" (Work item 341 needs an approval of type 'Approval' with state 'Pending' to be present.) and I am not able to save the work item. Can someone please tell me how to disable the approval tracking.I have checked the approval tracking for scope change and it is already clear.How to disable the approval for this work item type as I dont want approval functionality for this work item type??