diff --git a/lib/active_campaign/errors.rb b/lib/active_campaign/errors.rb
index 6132438..bf79ac6 100644
--- a/lib/active_campaign/errors.rb
+++ b/lib/active_campaign/errors.rb
@@ -28,14 +28,18 @@ def message
       if response.nil?
         super
       else
-        <<~MESSAGE
-          STATUS: #{response.status}
-          URL: #{env.url}
-          REQUEST HEADERS: #{env.request_headers}
-          RESPONSE_HEADERS: #{env.response_headers}
-          REQUEST_BODY: #{env.request_body}\n\n"
-          RESPONSE_BODY: #{response.body}\n\n"
-        MESSAGE
+        begin
+          <<~MESSAGE
+            STATUS: #{response.try(:status)}
+            URL: #{env.url}
+            REQUEST HEADERS: #{env.request_headers}
+            RESPONSE_HEADERS: #{env.response_headers}
+            REQUEST_BODY: #{env.request_body}\n\n"
+            RESPONSE_BODY: #{response.body}\n\n"
+          MESSAGE
+        rescue StandardError => e
+          super
+        end
       end
     end
 
diff --git a/lib/active_campaign/faraday/middleware/request.rb b/lib/active_campaign/faraday/middleware/request.rb
index 997b7a4..5bcdace 100644
--- a/lib/active_campaign/faraday/middleware/request.rb
+++ b/lib/active_campaign/faraday/middleware/request.rb
@@ -35,6 +35,8 @@ def normalize_body(env)
             logger.debug("Using body as is because group #{body}")
           elsif body.key?(:list)
             logger.debug("Using body as is because list #{body}")
+          elsif body.key?(:contacts) && body.key?(:callback)
+            logger.debug("Using body as is because contacts+callback #{body}")
           else
             body = transform_keys(body, :camelcase, :lower)
           end