Update error handling

app/services/uprn_client.rb

@@ -20,11 +20,11 @@ class UprnClient
   end
 
   def result
-    @result ||= begin
+    @result ||= if response.code == 200
                   parsed_response = JSON.parse(response.body)
                   parsed_response.dig("results", 0, "DPA") || parsed_response.dig("results", 0, "LPI")
-    rescue JSON::ParserError => e
-      Rails.logger.error("Failed to parse JSON response: #{e.message}")
+                else
+                  Rails.logger.error("Unexpected response code: #{response.code}")
                   nil
                 end
   end