Hello @viet
From the log you have attached I found that at some point you have a file which is shadowed by another file. Basically you have a model with the same name as another model and this might be causing your issue. Please try unique names for the reference models or the ones you have in path.
Warning:The file containing block diagram 'stateflow_uart' is shadowed by a file of the same name higher on the MATLAB path. This can cause unexpected behavior. For more information see "Avoiding Problems with Shadowed Files" in the Simulink documentation.
Regards,
Marius