added a new issue

Author: SnehaSudhirG

articles/automation/troubleshoot/runbooks.md

@@ -2,7 +2,7 @@
 title: Troubleshoot Azure Automation runbook issues
 description: This article tells how to troubleshoot and resolve issues with Azure Automation runbooks.
 services: automation
-ms.date: 09/16/2021
+ms.date: 02/06/2022
 ms.topic: troubleshooting
 ms.custom: has-adal-ref, devx-track-azurepowershell
 ---
@@ -11,6 +11,27 @@ ms.custom: has-adal-ref, devx-track-azurepowershell
 
  This article describes runbook issues that might occur and how to resolve them. For general information, see [Runbook execution in Azure Automation](../automation-runbook-execution.md).
 
+
+## Start-AzAutomationRunbook fails with runbookName does not match expected pattern error message
+
+### Issue
+When you run `Start-AzAutomationRunbook` to start specific runbooks it fails with the following error -
+`*runbookName does not match expected pattern '^[a-zA-Z]*-*[a-zA-Z0-9]*`
+
+```powershell
+`start-azautomationRunbook -Name "Test_2" -AutomationAccountName "AutomationParent" -ResourceGroupName "AutomationAccount" `Start-AzAutomationRunbook: `runbookname`does not match expected pattern '^[a-zA-Z]*-*[a-zA-Z0-9]*$'. 
+```
+
+## Cause
+
+Code that was introduced in [1.9.0 version](https://www.powershellgallery.com/packages/Az.Automation/1.9.0) of the Az.Automation module verifies the names of the runbooks to start and incorrectly flags runbooks with multiple "-" characters, or with an "_" character in the name, as invalid.
+
+## Workaround
+We recommend that you revert to [1.8.0 version](https://www.powershellgallery.com/packages/Az.Automation/1.8.0) of the module.
+
+## Resolution
+We plan to deploy a fix to address this issue.
+
 ## Diagnose runbook issues
 
 When you receive errors during runbook execution in Azure Automation, you can use the following steps to help diagnose the issues: