Why is my fastrtps having errors?

matthew@MatthewGan:~$ ros2 topic echo /cmd_vel2024-09-30 10:55:37.587 [RTPS_TRANSPORT_SHM Error] Failed init_port fastrtps_port -> Function open_port_internalt7429: open_and_lock_file failed -> Function open_port_internalmatthew@MatthewGan:~$ ros2 doctor --report | grep fastrtps2024-09-30 10:59:04.943 [RTPS_TRANSPORT_SHM Error] Failed init_port fastrtps_portt7429: open_and_lock_file failed -> Function open_port_internalrosidl_typesupport_fastrtps_cpp        : latest=6.2.7, local=6.2.7rmw_fastrtps_shared_cpp                : latest=2.2.2, local=2.2.2rosidl_typesupport_fastrtps_cpp        : latest=2.2.2, local=2.2.2rmw_fastrtps_cpp                       : latest=2.2.2, local=2.2.2fastrtps_cmake_module                  : latest=2.2.2, local=2.2.2rosidl_typesupport_fastrtps_c          : latest=2.2.2, local=2.2.2middleware name                        : rmw_fastrtps_cppmatthew@MatthewGan:~$ ros2 topic echo /cmd_vel2024-09-30 10:59:51.943 [RTPS_TRANSPORT_SHM Error] Failed init_port fastrtps_portt7429: open_and_lock_file failed -> Function open_port_internal