AgriDigital, an Australian blockchain-based agricultural platform, integrates IoT and blockchain to enhance supply chain transparency. By leveraging IoT sensors, it collects real-time data on crops, ensuring traceability from farm to consumer. Blockchain's immutability secures this data, preventing tampering and fostering trust. However, a notable case highlighted vulnerabilities: tampered IoT sensor data led to inaccurate crop quality records, exposing risks in data input processes. Despite blockchain’s tamper-proof ledger, the initial data collection stage remains susceptible to manipulation. AgriDigital addressed this by implementing stricter sensor verification and encryption protocols, like RC5, to ensure data integrity. This case underscores the need for robust security in IoT-blockchain systems to prevent data tampering, ensuring reliable agricultural data for decision-making and consumer trust.