i'm in construction industry...

say.. an overtime was rendered and paid from 6pm - 8pm but an hour deduction is incurred for tardiness in that particular day. is this legal?

also, payable overtime is set to 2 hrs minimal.. meaning 5:00 pm - 6:59 pm is not claimable thus a days work of 9 am - 7:59 will only result me a deduction of 1 hr and no overtime.