OVERTIME (ART. 87) does not have restriction as to the hours required by employer; as long as employees are being paid for the overtime work, its valid. So therefore, if an employee is required to work an overtime for 3-hours (9+3 = 12 hours of work) and get paid, that is valid or no violation.
However, according to labor standards of ILO, an employees can only be required for a maximum of 10 hours a day (working hours, break and overtime work).
Which now prevails between the two?