You can create a script or component to generate a random password that meets the requirements of the application. In your automation, you'll need to handle all possible password change errors (i.e. password is not unique, password is not complex enough, etc...) that your application can generate. Finally, code your solution such that the password is changed at every login. This will ensure it never gets out-of-date. Once you change the password, store it in the credential store or ASO manager so that when you change it again and it asks for the prior password, you will still have it.

but how it will recognize the password has changed or expired

You would need to interrogate that message if you needed to detect those scenarios by forcing them to happen while you were in interrogation mode. You'd also want to capture any expiring behaviors that might interfere with a normal login. My suggestion was to change it every time you login to prevent it from ever expiring or changing the normal login behavior. If the password changes, the bot would not likely be able fix itself, as whoever changed it would need to provide the correct credentials.

Remember that you are programming your robot like you might train a user. Making the process as standard as possible is easier than trying to handle variations in the process, even though it might contain more steps.

But What about Mainframe applications how can I handle this situation in mainframe because there ASO is not the proper solution for password change management.