Why do I receive an error that there is no named block state with the name for a custom Stateflow chart in R2018b?

Given is a custom Stateflow chart as show below,

When running the corresponding model the following error message appears,

There is no named block state with the name 'var1' in 'State1'.

see the following figure,

while right after the following Simulink subsystem within State1 opens up automatically in Simulink,

Why do I receive an error that there is no named block state with the name for a custom Stateflow chart in R2018b?

Answer 1

[MathWorks Support Team]

This error occurs because it is used a Simulink State instead of a standard State and variables are added in the title section of the Simulink State which is unexpected. To resolve the issue one has to replaced the Simulink States with standard States as shown in the following figure,