DMA checks for the uniqueness of the NetBIOS names, as well as the uniqueness of the DNS names of the source and target domains. Therefore, DMA will not migrate between domains where either of these two names are the same. A potential solution is to rename the Target domain. If this is not feasible, a workaround remedy is to set up a third 'intermediate' domain with a name that is not the same. DMA could migrate to the intermediate domain first and then to the final domain.
Please contact Technical Support to create a Support Request for any issues you encounter that are not addressed by the User Guide, any Knowledge Base articles found on the website, or current Hotfixes available for download.