Two thoughts come to mind:
1) Make sure remote registry service is enabled
2) How was the agent installed on your POS? One by one install for each POS or One image applied to several POS systems.
If it's one image applied to several POS, this may be an issue with duplicate GUIDS - You can spot check a couple POS systems to confirm GUIDS are duplicates:
HKLM\software\wow6432node\network associates\epolicy orchestrator\agent\agent guid