Faulty gas strut; If a sufficient amount of gas leaks while the back door is open, the gas struts may fail and pose a risk of injury  https://www.productsafety.gov.au/recall/toyota-motor-corporation-toyota-tarago-acr50-and-tarago-gsr50-my2019?fbclid=IwAR3DdaOf6BPioC8hp-Ae6Ss_zQrWoqhTcmBGRCSKwfr38yiT3VHkHWQy5C0