This computer is a member of a database availability group (DAG). It must be removed from the DAG before you can uninstall Exchange.

Unable to uninstall exchange server. Getting the below error message. I am sure, the servers is already removed the DAG, still I am getting the below error message.

Error:
This computer is a member of a database availability group (DAG). It must be removed from the DAG before you can uninstall Exchange.
For more information, visit: http://technet.microsoft.com/library(EXCHG.150)/ms.exch.setupreadiness.CannotUninstallClusterNode.aspx


To fix this issue, clean up the DAG from the system.
 run the command  Set-DatabaseAvailabilityGroup without any switch, that should fix the issue.
If the problem still persists, run the below command from an elevated prompt.
cluster node nodename /forcecleanup