Duplicate entries in SEPM

We are in progress of migrating the SEP clients to SEP 12.1.4 version, but once the migration completed we see duplicate entries of the clients in SEPM.

Any suggestion on how to mitigate this becoz we have nearly 1 Lac machine in our network, and if they will create duplicate entries it will effect our audit report. OR if there is any script or tool to delete the duplicate entries from SEPM.