I've been experiencing the same problem. The SDK works well creating, modifying and cancelling ARB subscriptions but continues to return "Active" for all cancelled and suspended requests (both in test and live environments).
To check subscriptions I'm using the C# SDK directly in my project like so:
PublicSharedFunction OpenGateway() AsSubscriptionGateway'pretend this is injected with IoC
Dim login As String = ConfigurationManager.AppSettings("ANetAPILoginID")
Dim transactionKey As String = ConfigurationManager.AppSettings("ANetAPITransactionKey")
Return New SubscriptionGateway(login, transactionKey, AuthorizeNet.ServiceMode.Live)
EndFunction
Public Shared Function CheckANetSubscriptionStatus(ByVal SubscriberID As String) As ARBSubscriptionStatusEnum
Dim gate As SubscriptionGateway = OpenGateway()
Dim response As ARBSubscriptionStatusEnum = gate.GetSubscriptionStatus(SubscriberID)
Return response
End Function
Any advice you could provide would be much appreciated!