Array of Busses in StateChart - Not able to extract the complete variable values in Stateflow

I am using Array of Bus as the input to a Statechart. I am not able to extract the complete values of variable 'a' in the state chart using

ArrayOfVarA1 = [data.a];

It is returning the following error:

Referencing a component from array of non-scalar values is not supported for code generation.

Transition '{Array...ta.a];}'
"[data.a]"
Component:Stateflow | Category:Coder error
Error while generating code for chart Chart.

If we want to individually store the data, the following method is working

    ArrayOfVarA1 = data(1).a;

Is there any method to store the 'a' values of my bus to a variable as Array. In Matlab it is working, but in Stateflow it is not working. What is the problem in this implementation?

My need is to get all the 'a' values of the bus FSignal to an array and to check is there any non zero values. It is used to find any failure messages. I am attaching the model for reference.