Under the version of MATLAB 2019a, Simulink inquires about communication error in ROS subscribe

1. Platform Description: use MATLAB / Simulink to build a model as a node to communicate with ROS master in Ubuntu system for custom MSG subscription and publishing. The original version is matlab 2017b, which can play bag packets for communication.

2. Problem Description: because of the need, matlab 2019a version is installed. During the simulation, the communication cannot be successful, and other settings are not changed. The error is shown in the figure. (the 2017 version has not been uninstalled, and friends' computers have not been uninstalled. The 2017 and 2019 versions have also been installed, both of which can communicate normally.)

3. We haven't found the right solution yet. We'd like to ask for help. Thank you very much.