I am also going through this situation. This is the circular which I had circulated. You can try this; maybe this works.
Office Timing Circular
You are all well aware of the timing for the commencement of the office. The office opens at 9:00 A.M daily, but after scrutiny of records, it has been observed that several employees are not adhering to this time and are found to be coming late, some as late as one to two hours.
This is an unacceptable practice. We are sure all of us want to be part of a success story, and no story can be successful without hard work and discipline. Let us all vow to be punctual and reach the office at 9:00 am sharp. This has to be strictly followed; failing which management will be constrained to take punitive action, which shall be detrimental to all concerned.
We need your cooperation on this to make the working environment healthy to work in.
Attendance Policy
a) First three late arrivals (up to 9:15 am): allowed
b) Second three late arrivals (after 9:15 am): Half Day
c) After this, all late arrivals will be marked as ABSENT for the day.
To be implemented with immediate effect.
Regards,
Ritika