obj.copy() don't copy all elements in class?

How to copy the all elements of obj in class or how to access elements using new obj to origianl elements?

backgournd experience can be found below.

the output of datastore is different by initial state - MATLAB Answers - MATLAB Central (mathworks.com)

[Angelo Yeo]

If you want a quicker reply from other contributors, it's helpful to leave a simple reproduction step and your pain points explicitly.