Hi @rockylin and @skalra18,
@rockylin:
I checked your site and found that you are not using paid membership pro plugin .
the issue which i stated in my previous reply is with the paid membership pro plugin .
Please check if there is any course product connected to the course which has subscription enabled .
Note that the wplms will discard the course duration while adding the user to course if the course product has subscription set and enabled.
refer :
http://prntscr.com/bmjfuz
@
skalra18: There is no such issue, just make sure your product subscription is not enabled, if enabled then make sure the duration is set properly or just the same as that of course.