Avamar Backup with VMware

Hi,

We had # of ESXi host and Avamar backup application integrated. We are running very fine.

But there is one issue we are facing it with Avamar. There are delta files which are leftover in the datastore. After releasing it from Avamar Proxy and deleting the delta file. We are able to run the backup successfully.

So actually my query is

1) Why delta files are left after successful completion of backup through Avamar ?

2) Where the issue is with VMware or with Avamar ?

3) How to fix the issue ?