PPPoE & Usermanager Problem

I have PPPoE Server with Mikrotik Version 3.25 with Level6 License, I’m Using Usermanager for Authentication and Accounting, the problem is: my users can login manytimes with the same Username and Password, In PPPoE Profile I checked the Only One: YES, but the Usermanager dosn’t work properly with PPPoE Profile when I choose the Group as the PPPoE Profile.

Note1: That Problem dosn’t found in Using Hotspot with Usermanager, Because of Usermanager Group work with Hotspot Profile.

Note2: When I use Secret to define a User there is no problem, that mean there is no connection between usermanager and PPPoE Profile.

Note3: in PPPoE Profile, the Option Only One has three attributes, NO, Yes, Default, the question what is default mean?? and what’s the default setting and How can I change the default setting??

if you use RADIUS, it should control simultaneous use, not RouterOS

p.s. as I understand, ‘Default’ means ‘the same value as in “default” profile’