Get-AzureVM is throwing an exception

i am using SMA to manager microsoft azure subscription and automate some tasks using sma runbooks , i had an online runbook as a test frist to get list of VMs its pretty simple worked for couple of times and now its always geenrating the following ERROR: 

Get-AzureVM : An error occurred while sending the request.

At SMA-Get-AzureVMs:9 char:9++ CategoryInfo          : CloseError: (:) [Get-AzureVM], HttpRequestException+ FullyQualifiedErrorId : Microsoft.WindowsAzure.Commands.ServiceManagement.IaaS.GetAzureVMCommand
machine have internet connectivity and no proxies involved in this 
any ideas?!