Assigning debug roles to few users of SAP ABAP program

Hope the role that you have added contains only one permission:

Object S_DEVELOP
   ACTVT = 03
   DEVCLASS = *
   OBJNAME = *
   OBJTYPE = DEBUG
   P_GROUP = *

Try to perform a permission trace usingTransaction ST01

If you still don’t find a check for the permission, there might be a problem in generating roles in the system. Sometimes when you add a role, it might add a different set of roles to such users.

There might be a different program written for Debugging. This can be checked using Transaction SU53 in the system. This can be used to display authorization data for user: