AD attributes update is not happening along with DN change

Version : IIQ 8.2p1
Our requirement is to update Distinguishedname of the active directory whenever there is company change happens for a vendor accounts. It needs few other attributes updates along with. Whenever this happens it is resulted with below error and the updates are not being done on the AD side too.

Could you please go through the below and suggest me some idea.

error: Failed to update attribute mail Error - The server is unwilling to process the request.

I was able to change DN by assigning new CN value in provisioning policy. Thanks !