Transaction Error when testing Authorize.Net Sandbox mode

receive the same error message. Did you solve this problem yet? 

If you are trying to test the sandbox mode, you need to enable it in the fields properties. Your form is not enabled for sandbox mode: http://www.jotform.us/form/61818365863163 

Please follow the steps described on this guide: https://www.jotform.com/help/221-How-to-Test-Authorize-net-Payment-Tool-on-Sandbox-Mode

Let us know if you need more help.