C-off - If Employee Comes On Duty On His Off Day?

Hello, I am working as HR with hospitality industry. In our hotel there are three shift i.e. morning evening and night. I want to know if some employee comes on duty on his off day and do morning evening and night shift than how many c- off will be considered .

Please ensure that no employee works for consecutive 3 shifts; it is not morally correct to ask an employee to work that way.
It will be legally correct to say that: he should be OT wages for 4 shifts. (3 worked+ 1 off day). If you follow comp-off practice for such working (it is not legally correct to do so) then he should be given 4 comp-offs.

To get one compensatory off at least six hours duty requires. employee cant put on work back to back on three shift.

Dear Sir,
Please clarify on following points --
a) Why was employee called for 3 shifts in a day ?
b) Who called him ?
c) What your company's shift policy says ?
This is for your information that if someone is being called off for a extra work on his off days, he /she is should be a given compensatory off against any leave availed by later.
Also, suggest you to be clear in drafting and executing company's policies as they help you and employees for one ground of understanding and also further calculation of comp. off.
Hope this will help you.
Regards,
Sapana