Notification Email is not working through Office 365

Hi,

I've configured to trigger email through Office 365 from MIM 2016. But I'm receiving the following error:

System.Web.Services: System.Net.WebException: The request failed
with HTTP status 401: Unauthorized. at
System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage
message, WebResponse response, Stream responseStream, Boolean asyncCall) at
System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName,
Object[] parameters) at
Microsoft.ResourceManagement.WebServices.Mail.Exchange.ExchangeServiceBinding.CreateItem(CreateItemType
CreateItem1) at
Microsoft.ResourceManagement.Mail.ExchangeProxy.ExecuteCreateItem(CreateItemType
request) at
Microsoft.ResourceManagement.Mail.ExchangeServer.SendNotification(NotificationMessage
message) at Microsoft.ResourceManagement.Mail.NotificationMessage.Send(Int32
timeoutInMilliseconds) at
Microsoft.ResourceManagement.Workflow.Hosting.SendMailWorkItemProcessor.SendMailMessage(MessageContent
messageContent, Int32 timeoutInMilliseconds) at
Microsoft.ResourceManagement.Workflow.Hosting.SendMailWorkItemProcessor.ProcessWorkItem(WorkItem
workItem)

Any help would be appreciate.

Thanks