Insubordinate Issue

Some people who are in the top management abuse their authority to their subordinates. In fact, they instruct them that are not included in their job responsibilities.
Is it insubordinate if they do not follow their managers or supervisors because it is not in the contract agreement?

It is always be insubordination if the rank and file don't follow their superior. But there is exemption to the rule. If the manager or supervisor has violated the COC when he/she imposed such rule to their subordinates. That is ground for dismissal and insubordination is deemed invalid.

However, if the manager and/or supervisor imposed rules that was agreed upon by the HR and the management, employees under them should abide but if they refuse to do so there is insubordination.

It is really not good to be rude to your superior at work you can exercise diligence and carry out the activity.