diff --git a/src/Bican/Roles/Traits/RoleHasRelations.php b/src/Bican/Roles/Traits/RoleHasRelations.php
index 16cc7c8..2f3b5ba 100644
--- a/src/Bican/Roles/Traits/RoleHasRelations.php
+++ b/src/Bican/Roles/Traits/RoleHasRelations.php
@@ -21,7 +21,12 @@ public function permissions()
      */
     public function users()
     {
-        return $this->belongsToMany(config('auth.model'))->withTimestamps();
+        if(isset(config('auth.model'))){
+            return $this->belongsToMany(config('auth.model'))->withTimestamps();
+        }
+        if(isset(config('auth.providers.users.model'))){
+            return $this->belongsToMany(config('auth.providers.users.model'))->withTimestamps();
+        }
     }
 
     /**