diff --git a/lib/faraday/uid2/middleware.rb b/lib/faraday/uid2/middleware.rb
index a841df2..c18af76 100644
--- a/lib/faraday/uid2/middleware.rb
+++ b/lib/faraday/uid2/middleware.rb
@@ -7,11 +7,11 @@
 module Faraday
   module Uid2
     class Middleware < Faraday::Middleware
-      def initialize(app, secret_key, is_refresh, options = {})
-        super(app, options)
+      def initialize(app, options = {})
+        super(app)
 
-        @key = Base64.decode64(secret_key)
-        @is_refresh = is_refresh
+        @key = Base64.decode64(options.fetch(:secret_key))
+        @is_refresh = options.fetch(:is_refresh, false)
       end
 
       def call(request_env)
diff --git a/lib/uid2/client.rb b/lib/uid2/client.rb
index fe185d6..0c35b31 100644
--- a/lib/uid2/client.rb
+++ b/lib/uid2/client.rb
@@ -30,7 +30,7 @@ def validate_token(token:, email: nil, email_hash: nil, phone: nil, phone_hash:
     end
 
     def refresh_token(refresh_token:, refresh_response_key:)
-      http(is_refresh: true, refresh_response_key: refresh_response_key).post("token/refresh", refresh_token).body
+      http(refresh_response_key: refresh_response_key).post("token/refresh", refresh_token).body
     end
 
     def get_salt_buckets(since: Time.now)
@@ -54,13 +54,13 @@ def credentials
       }
     end
 
-    def http(is_refresh: false, refresh_response_key: nil)
+    def http(refresh_response_key: nil)
       Faraday.new(
         url: base_url,
         headers: credentials
       ) do |f|
         f.request :json unless refresh_response_key
-        f.request :uid2_encryption, refresh_response_key || secret_key, is_refresh
+        f.request :uid2_encryption, {secret_key: (refresh_response_key || secret_key), is_refresh: !refresh_response_key.nil?}
         f.adapter :net_http_persistent
       end
     end