Answer:
As we know the internal controls are not effective after a passage of time because there are familiarity threats which might result in the unethical behavioral implications. So to prevent or detect the management unethical behavior, we can do the following things:
Segregation of Duties
Checking the effectiveness of the internal control after every year or semi year.
Using only company bank account for all the payments and receipt.
Redesigning policies of the organization to ensure effective working of the internal controls.
Bank reconciliation at the month end