V1/order/{id}/invoice setting capture = false still creates a paid invoice

[vaibhavtyagee]

I am on magento 2.2.2, i am trying to create a new invoice through api endpoint V1/order/{id}/invoice with a capture = false and notify = true , but its ignore the capture false argument and creates a paid invoice every time. Here is the json payload that i am sending 

{
   "capture": 'false',
    "items": { 
    		 "extension_attributes": {},
       		"order_item_id": 234,
       		"qty": 1
      		 },
  "notify": 'true'
}

invoice is getting created and notification email is being sent only the Capture = True is not working. 

Please help with the suggestions