The problem of assisting users in comprehending the robotic scenario information in a retail setting has been studied. To design the system, an integrated ontology composed of several IEEE standard ontologies and a labelled property graph (LPG)-based ontology modified from the Web Ontology Language (OWL)-based ontology was proposed to symbolize information in the robotic environment. Then, a knowledge graph (KG)-based chatbot was developed to provide natural language interaction with users. A case study in a retail setting was designed, and the results were analyzed. The effectiveness of our designed system has been experimentally validated in both static and dynamic scenarios, with at least 1.5 times improvements.