While DE-activating the asset number in asset form getting error Error : assets hierarchy exist for

Hi Team ,

While DE-activating the asset number in asset form getting error

Error : assets hierarchy exist for the asset

When  we verify in the SSM page asset configuration history asset doesn’t not contain any hierarchy with open Parent and child & there is no open work request and work order for that asset

1. One parent  is there with end dated

Please advise me how can  I de- active the asset

Thanks

Pavan Kumar Rudra