The attachments are deleting when using the test step REST API even when the Test Step does not belong to the Test

When using the test step REST API to update a Test Step, if you try remove an attachment from other Test, is showing an error message, but the attachment is deleted

ErrorMessage:

"Attachment with id 990 not found or does not belong to Step with id 1864." 

Endpoint: 

localhost:21000/rest/raven/1.0/api/test/{testKey}/step/{stepID}

Data:

{  
   "attachments":{  
      "remove":[  
         990
      ]
   }
}