Bounces statistic might not be collected when using EXM Delivery Cloud. The issue occurs because the EXM Delivery Cloud reads an incorrect property from a bounce message and thus fails to parse the contact. This results in 0% for bounce value in reports and the following errors in the logs:
23408 16:13:09 ERROR Bounce processing failed Exception: System.AggregateException Message: One or more errors occurred. Source: mscorlib at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions) at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken) at Sitecore.EDS.Providers.SparkPost.Tasks.BouncesTaskProcessor.HandleMessageEvents(CancellationToken cancellationToken, List`1 messageEventResponses) at Sitecore.EDS.Providers.SparkPost.Tasks.BaseTaskProcessor.OnProcess(ShortRunningTask task, CancellationToken cancellationToken) Nested Exception Exception: System.ArgumentNullException Message: value should not be null. Parameter name: value Source: Sitecore.Framework.Conditions at Sitecore.Framework.Conditions.RequiresValidator`1.ThrowExceptionCore(String condition, String additionalMessage, ConstraintViolationType type) at Sitecore.Framework.Conditions.Throw.ValueShouldNotBeNull[T](ConditionValidator`1 validator, String conditionDescription) at Sitecore.Framework.Conditions.ValidatorExtensions.IsNotNull[T](ConditionValidator`1 validator) at Sitecore.Modules.EmailCampaign.Core.Contacts.ContactIdentifierExtensions.ToContactIdentifier(String value) at Sitecore.EmailCampaign.Cm.Handlers.BouncedMessageHandler.HandleReportedMessages(ICollection`1 bouncedMessages) at Sitecore.EDS.Core.Reporting.DeliveryReportProvider`1.<HandleMessages>d__8.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Sitecore.EDS.Core.Reporting.DeliveryReportProvider`1.<HandleReportedMessages>d__7.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Sitecore.EDS.Core.Reporting.BounceManager.<HandleBouncedMessages>d__6.MoveNext()
To resolve the issue, consider one of the following options: