1 Month Plan
If you have a one month plan and you cancel the service within the first 15 days then you will have to pay half the amount and if you cancel after 15 days then you will have to pay the full amount.
Multi-Month Plan
If you have a multimonth plan and you are paying in monthly installments and you cancel the service before 15th of the month then you will have to pay half the amount and if you cancel the service after 15th then you will have to pay the full amount.
If you have paid the full amount of the multimonth plan in advance, then whenever you cancel the service, the calculation will be done keeping the 15th of the month in mind.