What is and isn't working, a little more information and someone may be able to help
Are you referring to Optus Sport?
Has it worked in the past or is it your first time watching Optus Sport?
What TV do you have? Are you watching on Fetch or a TV with the Optus Sport app? If it's the latter, have you tried logging out and in again?
If it's not Optus Sport, as Dane suggests, please provide some more info so we can better understand how we can try to help