Use instance variable

Author: garyhtou

app/services/user_service/enroll_sms_auth.rb

@@ -54,7 +54,7 @@ class SMSEnrollmentError < StandardError
     end
 
     def disallow_fresh_users
-      return if user.created_at < 1.day.ago
+      return if @user.created_at < 1.day.ago
 
       raise SMSEnrollmentError("Please wait at least 24 hours after creating your account before enrolling in SMS authentication.")
     end