please look at my answer
https://community.developer.authorize.net/t5/Integration-and-Testing/Accpet-Authorize-Net-Server-response-delay-errors/m-p/64407/highlight/true#M38308
HeyLooks like I was able to determine root of the issue. For
serialization we used classes from Authorize.NET library but for some
fields we used inherited classes (e.g. orderExType instead of orderType
). So XML that was sent to Authorize had additi...
