While there is no such thing as 2 hour for 1 day of validity.
If your service is down for more than 24 hours, you can call their accounts team (post the bill has been generated for the affected month and your support ticket(s) time should coincide) then you can get a credit on the billed amount pro-rated.
Note, that you need to reach out to account team via IVR and not technical support.
This works as I had to do this almost every month.
If you service was down for more than 8 days and continues to remain down and you have requested for a disconnection then they provide with a 15 days credit.