diff --git a/app/models/cart.rb b/app/models/cart.rb
index 92e7660..9c1732d 100644
--- a/app/models/cart.rb
+++ b/app/models/cart.rb
@@ -94,10 +94,6 @@ def validate_stock!
       end
     end
 
-    def add_payment_transaction(transaction)
-      self.class.requestor.custom("relationships/payment_transactions", {request_method: :post}, {id: id, data: [type: "payment_transactions", id: transaction.id.to_s]})
-    end
-
     def self.create(*args)
       if FlexCommerceApi.config.order_test_mode
         super({test: true})
diff --git a/lib/flex_commerce_api/version.rb b/lib/flex_commerce_api/version.rb
index 202a72e..8f1048e 100644
--- a/lib/flex_commerce_api/version.rb
+++ b/lib/flex_commerce_api/version.rb
@@ -1,4 +1,4 @@
 module FlexCommerceApi
-  VERSION = '0.6.25'
+  VERSION = '0.7.0'
   API_VERSION = 'v1'
 end