DA access Issue

[ajmalr]

We have implemented the DA access in our organization Everything is working fine.
1.DA client is able to access MP Server when it on Internet (http://servername/sms_mp/.sms_aut?mplist)
2.I able to access the SCCM server shares from DA client.
3.I have verified location services.log it is getting the correct AD site and MP
4.IPv6 Boundaries are created and Configured one of the Primary server where the DA server located.
Now we have issue in deploying the Packages.
1.content is distributed to DPs
2.DA client CCMcache noticed Empty folder is created.

Following error I noticed.
LocationService.Log - Calling back with empty distribution points list
CAS.log - Download request only, ignoring location update
Contenttransfer.log - CCTMJob::UpdateLocations - Received empty location update for CTM Job {A977A671-A81C-49B0-AE28-4687CE9DD2A1}
CTM job {A977A671-A81C-49B0-AE28-4687CE9DD2A1} suspended

I noticed content information is reaching the DA client but it is NOT able to find the DP and download the content Anyone can help me to fix this.
Let me know if another information required