work items removal from the stategies

I have changed or reset the High priority strategies for the customers to make sure that the High Priority Strategies are not active.

Post this I am attempting to remove the work items while all other work items are getting removed I am unable to remove one manual item which is basically "Call Customer" I get the error

"You cannot delete the work item template from this strategy template becuase active work item exists with this strategy template"

I again checked from the backend and the strategy is not active, but I do see this work item been shared across other strategies.