Rails 5 dropping some keys in params which contains non null values

I am moving from rails 3 to 5. I have a request to an API which accepts some parameter but is getting dropped in rails 5 for reasons I am not sure. The params which I recieved in Rails 3 was as below:

params = {"Envelope" => {"Body" => {"notifications" => {"Notification" => {"id =>" XYZ, "sObject" => {"data1" => ABC, "data2" => PQR}}}}}, "action" => XXX, "controller" => YYY, "format" => "xml", "auth" => AUTH_TOKEN, "entity" => ENTITY_NAME}

Whereas in Rails 5, the params I am receiving is:

params = <ActionController::Parameters {"entity"=>ENTITY_NAME, "auth"=>AUTH_TOKEN,  "format"=>"xml", "controller"=> YYY, "action"=> XXX} permitted: false>

How are the parameters getting dropped when the request is made?