On the OPTIONS request to api2.authorize.net/xml/v1/request.api it returns this error:
Error reading JToken from JsonReader. Path '', line 0, position 0.
And, of course thee resulting POST request also throws the usual "An error occurred during processing. Please try again."
I've looked all over the web for this, and there is very little information for this error.
Does anybody have any idea how to fix it?
Also seeing this on 2.3.3 using an Auth.net sandbox.
Did you ever find a solution to this issue? I have encountered the very same error, with little to go on in terms of debugging.