Non existant customer service

We ordered a king size combo 3. From the drive through at the new burger king in nelspruit. Upon arriving home we noticed there was a burger missing. Called the store and spoke to the manager. Was told that when we go there again she will comp. The missing burger. Without asking for any details from our side. How will she know who we are and when this took place without any details regading the complaint? Customer service is not a priority for sure.